System for the treating biomaterial waste streams

ABSTRACT

A process for treating a biomaterial waste stream is described. The process may form part of a waste fermentation system. The treating process can degrade at least a portion of the biomaterial waste stream into other components or materials. These other components or materials may be reintroduced into a fermentation process as a nutrient for a fermenting organism.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. 119(e) of U.S.Provisional Application Ser. Nos. 60/572,187; 60/572,226; 60/572,166;60/572,179; 60/572,206, 60/571,996; and 60/571,959; filed May 18, 2004,each of which is expressly incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to processes and apparatus for treating abiomaterial waste stream. The processes and apparatus can be used torecover or remove components for modification and reintroduction into afermentation process.

BACKGROUND

The disposal of biomaterial waste, such as animal waste, human waste,and waste from food processing plants, is becoming increasinglydifficult. Large quantities of waste are produced every day fromfamilies in urban and rural areas, from industrial sources, such as fromfood processing plants and slaughterhouses, and from agriculturalsources, such as livestock and poultry feeding operations. The wastemust be disposed of in a way that protects the environment, inparticular air and water, from the pollutants in such waste (e.g.,carbon, phosphorus, and nitrogen). Common methods of biomaterial wastedisposal presently include land application of the waste, disposal ofthe waste in sanitary landfills, and disposal of the waste by processingin composting plants. However, the large volume of waste being currentlygenerated cannot be adequately handled by using the presently availablemethods for waste disposal.

In fact, the Environmental Protection Agency has designated more than40% of the streams, rivers, and lakes in the United States as beingalready impaired or as showing signs of impairment as environments foraquatic life. As a consequence of the adverse impact of biomaterialwaste on the environment, the Environmental Protection Agency isimposing increasingly strict regulations for waste disposal to protectthe environment from the pollutants present in biomaterial waste. Inparticular, the Environmental Protection Agency is proposing to limitland application of waste from livestock and poultry to a crop's needfor phosphorus, which will greatly increase the acreage needed for landapplication of waste and may run many livestock and poultry operationsout of business. Accordingly, there is a need for efficient processesfor disposing of biomaterial waste streams from a variety of sources,such as agricultural and industrial sources of waste, human waste, andthe like.

SUMMARY OF THE INVENTION

Processes and apparatus are described herein for treating a biomaterialwaste stream from virtually any source including, but not limited to,animal waste, animal manure, cellulosistic solid waste, feathers, hair,whey broth from cheese production or biomaterial waste streams fromother foodstuffs, broth remediation from alcohol production or yeastproduction, tannery waste, slaughterhouse waste, tallow waste fromrendering processes, tallow waste from used fats and/or cooking oils,landscaping waste, waste derived from plants, paper processing waste,land fill waste, and the like. The waste derived from animals that maybe treated using the processes and apparatus described herein can be,for example, from ruminants, including semi, partial, and fullruminants, swine, beef cattle, dairy cattle, horses, poultry, includinglayers and broilers, and the like. The waste derived from plants can be,for example, waste from hay, leaves, weeds, sawdust, or wood and can be,for example, yard waste, landscaping waste, agricultural crop waste,forest waste, pasture waste, or grassland waste. The waste derived fromfoodstuffs can be fruit and vegetable processing waste, fish and meatprocessing wastes, bakery product waste, waste from cheese production,used fats and cooking oils, and the like.

In one embodiment, processes and apparatus are described for treatingwaste from barn animals, including beef cattle, dairy cattle, horses,and the like. In another embodiment, processes and apparatus aredescribed for treating waste from swine. In another embodiment,processes and apparatus are described for treating waste from poultry,including chickens, turkeys, ducks, and the like. In another embodiment,processes and apparatus are described for treating waste from foodprocessing, including cheese whey. In another embodiment, processes andapparatus are described for treating waste from food processing andpreparation, including tallow waste, waste fats, and waste oils.

The processes and apparatus described herein include biomaterial wastecollection units, dissolved solid and undissolved solid precipitationunits, lignin removal units, solid/liquid separation units, chemicalprocessing units, enzymatic processing units, microbial processingunits, and pH adjustment units, and the like. The processes andapparatus described herein include various combinations of these andother units to form modules for treating biomaterial waste streams. Suchmodules may be used independently or may be used as part of a largersystem that includes other treatment or processing steps, such asfermentation systems for treating or disposing of biomaterial wastestreams. The chemical processing units described herein include acidhydrolysis units, mild acid hydrolysis units, base hydrolysis units,saponification units, and the like. The combination of units and/ormodules assembled to form the various processes and apparatus describedherein is dependent upon the components of the biomaterial waste streamto be treated.

The various units described herein may be assembled into modules fortreating particular biomaterial waste streams or for treating particularcomponents found in various biomaterial waste streams. The processes andapparatus described herein include modules for removing fiber-basedbiomaterial waste, such as hay, straw, bedding straw, sawdust,celluloses, hemicelluloses, cellulose-related components, othercellulosistic material, feathers, hair, and the like. The processes andapparatus described herein include modules for removing proteins,polypeptides, peptides, organic acids, organic phosphates, organicamines, complex starches, and the like. The processes and apparatusdescribed herein include modules for precipitating proteins,polypeptides, peptides, organic acids, organic phosphates, organicamines, complex starches, and the like, for subsequent removal.

The processes and apparatus described herein include modules fordegrading fiber-based biomaterial waste, such as hay, straw, beddingstraw, sawdust, celluloses, hemicelluloses, cellulose relatedcomponents, other cellulosistic material, and the like. The processesand apparatus described herein include modules for degrading proteins,polypeptides, peptides, feathers, hair, organic acids, organicphosphates, organic amines, complex starches, and the like.

The processes and apparatus described herein include modules forreintroducing degraded fiber-based biomaterial waste, such as hay,straw, bedding straw, sawdust, celluloses, hemicelluloses, celluloserelated components, other cellulosistic material, feathers, hair, andthe like into fermentation processes. The processes and apparatusdescribed herein include modules for reintroducing degraded grains, andthe like into fermentation processes. The processes and apparatusdescribed herein include modules for reintroducing degraded proteins,polypeptides, peptides, organic acids, organic phosphates, organicamines, complex starches, and the like into fermentation processes. Theprocesses and apparatus described herein include modules forreintroducing degraded tallows, fats, and oils, and the like intofermentation processes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of one illustrative embodiment of a system forprocessing a biomaterial waste stream.

FIG. 2A is a front elevational view of one illustrative embodiment ofthe sand separation unit forming part of the waste stream pre-treatmentsystem in the biomaterial waste stream processing system of FIG. 1.

FIG. 2B is a side elevational view of the sand separation unit of FIG.2A.

FIG. 3 is a schematic diagram of one illustrative embodiment of acontrol system for controlling the sand separation unit of FIGS. 1-2B.

FIGS. 4A and 4B show a flowchart of one illustrative embodiment of asoftware control algorithm for controlling the sand separation unit ofFIGS. 1-2B via the control system of FIG. 3.

FIG. 5A is a side elevational view of one illustrative embodiment of theliquid/solid separation unit forming part of the waste streampre-treatment system in the biomaterial waste stream processing systemof FIG. 1.

FIG. 5B is a front elevational view of the liquid solid separation unitof FIG. 5A.

FIG. 6 is a schematic diagram of one illustrative embodiment of acontrol system for controlling the liquid/solid separation unit of FIGS.1 and 5A-5B.

FIG. 7 is a flowchart of one illustrative embodiment of a softwarecontrol algorithm for controlling the liquid/solid separation unit ofFIGS. 1 and 5A-5B via the control system of FIG. 6.

FIG. 8A is a schematic diagram of one illustrative embodiment of the pHadjustment unit and corresponding control system that forms part of thewaste stream pre-treatment system in the biomaterial waste streamprocessing system of FIG. 1.

FIG. 8B is a schematic diagram of another illustrative embodiment of thepH adjustment unit and corresponding control system that forms part ofthe waste stream pre-treatment system in the biomaterial waste streamprocessing system of FIG. 1.

FIG. 8C is a diagrammatic representation of one illustrative embodimentof the settling tank forming part of the pH adjustment unit of FIG. 8B.

FIG. 8D is a cross-sectional view of the settling tank of FIG. 8C viewedalong section lines 8D-8D.

FIG. 8E is a diagrammatic representation of the settling tank of FIGS.8C and 8D illustrating operation thereof.

FIG. 9 is a flowchart of one illustrative embodiment of a softwarecontrol algorithm for controlling the pH adjustment unit of FIG. 1 viathe control system of either of FIGS. 8A and 8B.

FIG. 10 is a schematic diagram of one illustrative embodiment of the airsystem and corresponding control system that forms part of thebiomaterial waste stream processing system of FIG. 1.

FIG. 11 is a schematic diagram of one illustrative embodiment of thewater system and corresponding control system that forms part of thebiomaterial waste stream processing system of FIG. 1.

FIG. 12 is a block diagram of one illustrative embodiment of the wastefermentation system forming part of the biomaterial waste processingsystem of FIG. 1.

FIG. 13A is a schematic diagram of one illustrative embodiment of thesterilization unit and corresponding control system that forms part ofthe waste fermentation system of FIG. 12.

FIG. 13B is a schematic diagram of another illustrative embodiment ofthe sterilization unit and corresponding control system that forms partof the waste fermentation system of FIG. 12.

FIG. 13C is a cross-sectional view of one illustrative embodiment ofeither of the settling tanks forming part of the sterilization system ofFIG. 13B.

FIG. 13D is a diagrammatic representation of one of the number oftruncated cone-topped cylinders positioned within the settling tank ofFIG. 13B.

FIG. 13E is a magnified cross-sectional view a portion of the settlingtank of FIG. 13C illustrating operation thereof.

FIG. 13F is a magnified cross-sectional view of another portion of thesettling tank of FIG. 13C illustrating operation thereof.

FIGS. 14A-14C show a flowchart of one illustrative embodiment of asoftware control algorithm for controlling the sterilization unit ofeither of FIGS. 13A and 13B.

FIG. 15 is a schematic diagram of one illustrative embodiment of thesteam unit and corresponding control system that forms part of the wastefermentation system of FIG. 12.

FIG. 16 is a flowchart of one illustrative embodiment of a softwarecontrol algorithm for controlling the steam unit of FIG. 15.

FIG. 17 is a schematic diagram of one illustrative embodiment of thecooling tower unit and corresponding control system that forms part ofthe waste fermentation system of FIG. 12.

FIGS. 18A-18B show a flowchart of one illustrative embodiment of asoftware control algorithm for controlling the cooling tower unit ofFIG. 17.

FIG. 19 is a diagrammatic representation of one illustrative embodimentof the fermentation unit forming part of the waste fermentation systemof FIG. 12.

FIG. 20 is a diagrammatic illustration of the general operation ofeither of the fermentation tanks of FIG. 19 in a normal, continuous flowoperational mode.

FIG. 21 is a diagrammatic illustration of the operation of the airspargers and fermenting organism collection cone in either of thefermentation tanks of FIG. 19 in a fermenting organism reductionoperational mode.

FIG. 22 is a diagrammatic illustration of the operation of the airspargers and fermenting organism collection cone in either of thefermentation tanks of FIG. 19 in the normal, continuous flow operationalmode.

FIG. 23A is a front elevational view of one illustrative embodiment ofthe first fermentation tank of FIG. 19.

FIG. 23B is a magnified front elevational view of the lower portion ofthe first fermentation tank of FIG. 23A illustrating some of thestructural details of the air spargers and fermenting organismcollection cone.

FIG. 23C is a cross-sectional view of the lower portion of the firstfermentation tank of FIG. 23B viewed along section lines 23C-23C.

FIG. 24A is a front elevational view of one illustrative embodiment ofthe second fermentation tank of FIG. 19.

FIG. 24B is a cross sectional view of the lower portion of the secondfermentation tank of FIG. 24A viewed along section lines 24B,C-24B,C andillustrating some of the structural details of the outer air sparger.

FIG. 24C is a cross sectional view of the lower portion of the secondfermentation tank of FIG. 24A viewed along section lines 24B,C-24B,C andillustrating some of the structural details of the inner air sparger.

FIG. 25 is a schematic diagram of one illustrative embodiment of acontrol system for controlling the fermentation unit of FIGS. 12 and19-24C.

FIGS. 26A-26H show a flowchart of one illustrative embodiment of asoftware control algorithm for controlling the fermentation unit ofFIGS. 12 and 19-24C via the control system of FIG. 25.

FIG. 27A is a schematic diagram of one illustrative embodiment of thepasteurization unit and corresponding control system that forms part ofthe waste fermentation system of FIG. 12.

FIG. 27B is a schematic diagram of another illustrative embodiment ofthe pasteurization unit and corresponding control system that forms partof the waste fermentation system of FIG. 12.

FIG. 28 is a flowchart of one illustrative embodiment of a softwarecontrol algorithm for controlling the pasteurization unit of either ofFIGS. 27A and 27B.

FIG. 29 is a schematic diagram of one illustrative embodiment of theresidual liquid processing unit and corresponding control system thatforms part of the biomaterial waste processing system of FIG. 1.

FIG. 30 is a flowchart of one illustrative embodiment of a softwarecontrol algorithm for controlling the residual liquid processing unit ofFIG. 29.

FIG. 31 shows the catalysis of flocculation of Pichia stipitis in thepresence of 0.125 g/L of xanthan gum and increasing amounts of iron inppm (x-axis). Flocculation was measured by allowing the yeast to settlefor 4 minutes, taking samples from the supernatant, and counting thecells using a hemocytometer.

FIG. 32 shows the catalysis of flocculation of Pichia stipitis in thepresence of various xanthan gum (see legend) and iron concentrations(x-axis). Flocculation was measured as described in the description ofFIG. 31 above.

FIG. 33 shows the iron concentrations in ppm in the supernatant (y-axis)for Pichia stipitis flocculated in the presence of 0.0125 g/L of xanthangum and increasing amounts in ppm of iron (x-axis).

FIG. 34 shows the catalysis of flocculation of Saccharomyces cerevisiaein the presence of increasing amounts in ppm of iron (x-axis) and undercontrol conditions (diamonds), in the presence of 0.5 g/L of magnesium(triangles), at pH 7.11 (crosses), or in the presence of 2.5 g/L of NaCl(pluses).

FIG. 35 shows the iron concentration in the supernatant in ppm (y-axis)during catalyzed flocculation of Saccharomyces cerevisiae with 0.025 g/Lof xanthan gum and increasing concentrations of iron (x-axis) in thepresence of 0.5 g/L of magnesium (squares), at pH 7.11 (triangles), orin the presence of 2.5 g/L of NaCl (crosses).

FIG. 36 shows the percentage of yeast in the flocculating form (y-axis)versus the percentage of dilution of the sample (x-axis) forSaccharomyces cerevisiae (diamonds), Pichia stipitis (triangles), andCandida utilis (squares) flocculated in the presence of 0.025 g/L ofxanthan gum and 15 ppm (S. cerevisiae and C. utilis) or 20 ppm (P.stipitis) of iron.

FIG. 37 shows the settling rate (inches/minute) (cennimeters/minute) forSaccharomyces cerevisiae, Pichia stipitis, Kluyveromyces lactis, andCandida utilis flocculated in the presence of 0.025 g/L of xanthan gum(0.025 g/L) and 15 ppm of iron.

FIG. 38 shows the catalysis of flocculation of Saccharomyces cerevisiaeflocculated in the presence of 0.025 g/L of xanthan gum and in thepresence of 5 ppm (diamonds), 10 ppm (squares), or 15 ppm (triangles) ofiron at increasing pH (x-axis).

FIG. 39 shows the catalysis of flocculation of Saccharomyces cerevisiaeflocculated in the presence of 0.025 g/L of xanthan gum and in thepresence of 5 ppm of iron and 2 g/L of xylitol (diamonds), 10 ppm ofiron and 4 g/L of xylitol (squares), or 15 ppm of iron and 6 g/L ofxylitol (triangles) at increasing pH (x-axis).

FIG. 40 shows the catalysis of flocculation of E. coli flocculated inthe presence of 0.025 g/L of xanthan gum and in the presence ofincreasing concentrations of iron (x-axis) at a pH of 5 (diamonds) or 9(squares).

FIG. 41 shows the catalysis of flocculation of Bacillus sp. flocculatedin the presence of 0.025 g/L of xanthan gum and in the presence ofincreasing concentrations of iron (x-axis) at a pH of 5 (diamonds) or 9(squares).

FIG. 42 shows the catalysis of flocculation of E. coli flocculated inthe presence of 0.025 g/L of xanthan gum and in the presence ofincreasing concentrations of iron (x-axis) at pH's of 3, 5, 7, 9, and11.

FIG. 43 shows the catalysis of flocculation of Bacillus sp. flocculatedin the presence of 0.025 g/L of xanthan gum and in the presence ofincreasing concentrations of iron (x-axis) at pH's of 3, 5, 7, 9, and11.

FIGS. 44A and 44B show an illustrative system for treating a ruminantwaste stream.

FIG. 44C shows an illustrative system for removing lignin.

FIG. 44D shows an illustrative system for acid hydrolysis.

FIG. 45A shows an illustrative system for treating a swine waste stream.

FIG. 45B shows an illustrative embodiment of a swine waste receptacle.

FIG. 46 shows an illustrative system for treating a cheese processingwaste stream.

FIG. 47 shows an illustrative correlation between conductivity and pH.

FIG. 48 shows an illustrative system for treating fat and oil waste.

FIG. 49 shows an illustrative system for removing dissolved and/orundissolved solids from an aqueous solution.

FIGS. 50A and 50B show a front view and a top view, respectively, of anillustrative aggregation tank for removing dissolved and/or undissolvedsolids from an aqueous solution.

FIG. 51 shows an illustrative process for disposing of a biomaterialwaste stream, including an optional pre-processing step for treatingsolids removed from the biomaterial waste stream, and an optionalpost-processing step for removing dissolved and undissolved solids froma biomaterial waste stream.

FIG. 52 shows chromatographic traces for various samples of barn flushliquid waste based on changes in pH, added aluminum, heating, andspiking with Bovine Carbonic Anhydrase.

DETAILED DESCRIPTION Illustrative Embodiments of a System for Processinga Biomaterial Waste Stream

For the purpose of promoting an understanding of the principles of thisdisclosure, reference will now be made to one or more embodimentsillustrated in the drawings and specific language will be used todescribe the same. It will nevertheless be understood that no limitationof the scope of the claims appended hereto is thereby intended.

Referring to FIG. 1, a block diagram of one illustrative embodiment 10of a system for processing a biomaterial waste stream is shown. Thesystem 10 illustrated in FIG. 1 will be described in detail herein asbeing operable to process a continuous stream or flow of liquefiedbiomaterial waste, having dilute, and/or variable, nutrient content, ina manner that converts the biomaterial waste stream to a fermentingorganism, such as yeast, and water. In the following description ofsystem 10 and its various components, illustrative embodiments will beshown and described with particular emphasis on processing a biomaterialwaste stream in the form of animal waste, such as that produced bylivestock, although it will be understood that system 10 is operable toprocess liquid or liquefied biomaterial waste streams produced by othersources such as food processing plants, slaughterhouses and other animalor fish processing facilities, agricultural sources, such as livestockand poultry feeding operations, human waste processing facilities, andother sources of organic waste. In any case, the fermenting organismproduced by this process may have value, such as a food supplement forlivestock or other animals, and the water produced by the process isgenerally safe for disposal as ground water.

System 10 includes a waste stream pre-treatment system 12 configured topre-treat liquefied biomaterial waste, and to supply a resulting liquidbiomaterial waste stream to a waste fermentation system 14 via conduit42. The waste stream pre-treatment system 12 includes a sand separationunit 18 having a liquefied waste inlet, LWI, for receiving liquefiedbiomaterial waste from a liquefied waste source 20 via conduit 22. Inthe illustrated embodiment, the liquefied biomaterial waste source 20may be an animal waste storage lagoon or other animal waste storagearrangement having liquefied animal waste stored therein, or may insteadbe another waste processing system configured to process animal waste ina manner that produces liquefied animal waste and that supplies a streamof such liquefied animal waste to the waste stream pre-treatment system12. One example of such a waste processing system may be a processingsystem configured to receive animal waste in the form of a dry orsemi-dry composition of sand and animal waste, and to hydrate andseparate the composition into bulk sand and liquefied animal waste in amanner that produces a continuous stream of the liquefied animal waste.One embodiment of such a sand and animal waste composition processingsystem is disclosed in PCT/US2005/______, entitled SAND AND ANIMAL WASTESEPARATION SYSTEM (attorney docket no. 35479-77857), which is assignedto the assignee of the present invention, and incorporated herein byreference.

The sand separation unit 18 further includes a water inlet, WI,receiving fresh water from a water system 24 via water inlet conduit 26,a sand outlet, SNDO, producing bulk sand via sand outlet conduit 28, anda liquefied waste outlet, LWO, supplying liquefied waste to a liquefiedwaste conduit 32. In the illustrated embodiment, the water system 24 isa water processing system operable to receive tap water from aconventional tap water source (not shown) via conduit 25, to conditionthe water via conventional water conditioning; e.g., softening,techniques, and to supply the conditioned water to water conduit 26, andone illustrative embodiment of such a water system will be described indetail hereinafter with respect to FIG. 11. Alternatively, the watersystem 24 may be a conventional source of tap water, wherein such tapwater may or may not be conditioned.

In the illustrated embodiment, the sand separation unit 18 is operableto separate sand from the liquefied waste supplied by the liquefiedwaste source 20, and to supply the resulting liquefied waste to aliquefied waste conduit 32. It will be understood that in embodiments ofsystem 10 wherein the liquefied waste source 20 is a sand and wastecomposition processing system of the type described hereinabove, thesand separation unit 18 may also be included within some implementationsof the waste stream pre-treatment system 12 to act as a secondary sandseparation unit, or may in other implementations be omitted from thewaste stream pre-treatment system 12. Whether to include the sandseparation unit 18 in such embodiments will depend on a number offactors including the volume of sand, or sand to waste ratio in the sandand animal waste composition, the sand extraction capacity of the sandand waste composition processing system, the volume of sand in, or sandto waste ratio of, the liquefied waste supplied to the sand separationunit 18, the maximum allowable sand volume in, or sand to waste ratioof, the liquefied waste stream provided to the remaining components ofthe biomaterial waste processing system 10, and the like. In any case,further details relating to one illustrative structure, control systemand control strategy for the sand separation unit 18 will be describedin detail hereinafter with respect to FIGS. 2A-4B.

The waste stream pretreatment system 12 further includes a liquid/solidseparation unit 30 having a liquefied waste inlet, LWI, for receivingthe liquefied biomaterial waste stream from the sand separation unit 18,a water inlet, WI, receiving fresh water from water system 24 via thewater inlet conduit 26, a small particle outlet, SPO, coupled to a smallparticle outlet conduit 34, a large particle outlet, LPO, coupled to alarge particle outlet conduit 36, and a liquid waste outlet, LWO,supplying liquid waste to a liquid waste conduit 40. In the illustratedembodiment, the liquid/solid separation unit 30 is operable to separatewaste particles larger than a predefined size from the liquefied wastestream supplied by the sand separation unit 18, and to produce aresulting liquid waste, from which small waste particles are furtherextracted, and to supply the resulting liquid waste to the liquid wasteconduit 40. Further details relating to one illustrative structure,control system and control strategy for the liquid/solid separation unit30 will be described in detail hereinafter with respect to FIGS. 5A-7.

The waste stream pre-treatment system 12 further includes a pHadjustment unit 38 having a liquid waste inlet, LWI, for receiving theliquid biomaterial waste stream from the liquid/solid separation unit 30and a liquid waste outlet, LWO, supplying liquid waste to a liquid wasteconduit 42. In the illustrated embodiment, the pH adjustment unit 38 isoperable to selectively adjust the pH level of the liquid waste streamsupplied to conduit 42 to a target pH level. Further details relating toone illustrative structure, control system and control strategy for thepH adjustment unit 38 will be described in detail hereinafter withrespect to FIGS. 8A-9.

The liquid biomaterial waste stream exiting the waste streampre-treatment system 12 is supplied to a liquid waste inlet, LWI, of thewaste fermentation system 14 via conduit 42. It will be understood thatone or more of the components of the waste stream pre-treatment system12 just described may not be strictly required in some embodiments ofthe biomaterial waste processing system 10 for effective operation thewaste fermentation system 14. However, inclusion of the components ofthe pre-treatment system 12 illustrated in FIG. 1 provide foroptimization of the some of the physical properties of the liquid wastestream supplied to the waste fermentation system 14 in embodimentswherein the liquefied biomaterial waste is liquefied animal waste. Inany case, the waste fermentation system 14 further includes a first seedinlet, SD1, fluidly coupled to a first seed source 44 via conduit 46,and a second seed inlet, SD2, fluidly coupled to a second seed source 48via conduit 50. Seed inlet ports SD1 and SD2 are each configured toreceive a microorganism seed from a corresponding seed source to beginfermentation within the waste fermentation system 14 as will bedescribed in greater detail hereinafter. The waste fermentation system14 further includes a chemical inlet, CHI, fluidly coupled to a chemicalsource 52 via conduit 54, wherein the chemical inlet, CHI, is configuredto receive a chemical solution for conditioning water used by one ormore of the components of the waste fermentation system 14.

An air system 56 is coupled to the waste fermentation system 14 via anumber of conduits, and is configured to supply pressurized air for useby one or more components of the waste fermentation system 14. In theillustrated embodiment, the waste fermentation system 14 includes afirst inner air sparger inlet, F1I, receiving pressurized air from theair system 56 via conduit 58, a first outer air sparger inlet, F1O,receiving pressurized air from the air system 56 via conduit 60, asecond inner air sparger inlet, F2I, receiving pressurized air from airsystem 56 via conduit 62, a steam outlet, ST, providing steam to the airsystem 56 via conduit 64, and a seed steam inlet, F12S, receivingpressurized steam from the air system 56 via conduit 66. The air system56 further includes a drain outlet to allow draining of condensed watervia a drain conduit 67. One illustrative embodiment of the air system 56will be described in detail hereinafter with respect to FIG. 10.

The waste fermentation system 14 further includes a gas outlet, GO,fluidly coupled to a gas outlet conduit 68, wherein the wastefermentation system 14 is operable to expel exhaust gases; e.g., exhaustair, resulting from the waste fermentation process. A product outletport, PO, of the waste fermentation system 14 is fluidly coupled to aproduct outlet conduit 70, and the fermenting organism resulting fromthe fermentation process within the waste fermentation system 14 may beextracted from the waste fermentation system 14 via conduit 70 andcollected in a suitable product receiving container 72. A residualliquid outlet, RLO, of the waste fermentation system 14 is fluidlycoupled to a residual liquid conduit 74, and the waste fermentationsystem 14 is configured to expel residual liquid resulting from thefermentation process therein via conduit 74. A liquid waste returnoutlet, LWR, of the waste fermentation system 14 is fluidly coupled to aliquid waste return conduit 76, and the waste fermentation system 14 isconfigured to expel waste water resulting from the operation of thewaste fermentation system 14 via conduit 76. One illustrative embodimentof the waste fermentation system 14 will be described in detailhereinafter with respect to FIGS. 12-28.

The biomaterial waste processing system 10 further includes a residualliquid post-processing unit 16 having a residual liquid inlet, RLI,receiving via conduit 74 the residual liquid produced by the wastefermentation system 14, a first liquid outlet, LO1, fluidly coupled to aliquid outlet conduit 82, a second liquid outlet, LO2, fluidly connectedto the liquid waste return conduit 76 via conduit 78, and a precipitatedwaste outlet, PWO, fluidly coupled to a precipitated waste outletconduit 80. In the illustrated embodiment, the residual liquid producedby the waste fermentation system 14 is the residual liquid resultingfrom fermentation of the liquid biomaterial waste stream. As such, thisresidual liquid may include a variable residual waste content, and theresidual liquid processing unit 16 is configured to precipitate at leasta substantial portion of the residual waste from the residual liquid andexpel the resulting substantially waste-free, cleaned water via theliquid waste conduit 82 in the form of ground water. In cases where theliquid resulting from the precipitation process is not sufficientlyclean to expel from the residual liquid processing unit in the form ofground water, it may be routed back to the liquefied waste source 20 viathe liquid waste return conduit 76. One illustrative embodiment of theresidual liquid processing unit 16 will be described in detailhereinafter with respect to FIGS. 29-30.

At least some of the operational aspects of the biomaterial wasteprocessing system 10 are electronically controlled, and system 10 mayaccordingly include any number of control circuits for executing suchcontrol. In one embodiment, for example, electronic control of thebiomaterial waste processing system 10 is accomplished via a number ofconventional programmable logic circuits (PLCs) distributed throughoutthe system 10, wherein such PLCs have a number of inputs for receivingsensory data produced by one or more sensors and a number of outputsconfigured to control one or more system actuators. The number of PLCsinclude microprocessor-based controllers and on-board memory, and may beconfigured to communicate with each other yet operate independently. Inone illustrative embodiment, such PLCs are commercially availablethrough ControLLogix, Inc.

In the embodiment of system 10 illustrated in FIG. 1, three suchprogrammable logic circuits are shown; a first PLC 102 configured tocontrol the operation of the waste stream pre-treatment system 12, asecond PLC 120 configured to control operation of the waste fermentationsystem 14 and a third PLC 140 configured to control operation of theresidual liquid processing unit 16. It will be understood that onlythree such PLC circuits are shown in FIG. 1 for ease of illustration andsubsequent description of the operation of the system 10, and that apractical implementation of the system 10 may include any number of PLCsdistributed throughout the waste stream pre-treatment system 12, thewaste fermentation system 14 and the residual liquid processing unit 16to effectuate electronic control of the biomaterial waste processingsystem 10.

In the illustrated embodiment, the waste stream pre-treatment system 12includes a number, u, of sensors 104 ₁-104 _(u) operable to sense acorresponding number of physical operating conditions of the variouscomponents 18, 30 and 38 of the waste stream pretreatment system 12, andto supply such sensory information in the form of analog sensor signalsto corresponding sensor inputs of the PLC circuit 102 via correspondingsignal paths 106 ₁-106 _(u), wherein “u” may be any positive integer. Inembodiments of system 10 wherein the liquefied waste source 20 is aliquefied waste storage arrangement, such as a liquefied waste storagelagoon, the liquefied waste source 20 includes a level sensor 114operable to sense the level of liquefied waste in the liquefied wastesource 20, and to supply this sensory information in the form of anotheranalog sensor signal to PLC circuit 102 via signal path 118. The PLCcircuit 102 is, in turn, operable to process the sensory data providedby the number of sensors 104 ₁-104 _(u) and 114, and producecorresponding analog actuator signals, which are then provided viasignal paths 112 ₁-112 _(v) to corresponding actuators associated withthe various components 18, 30 and 38 of the waste stream pretreatmentsystem 12 to effectuate control of the various components 18, 30 and 38,wherein “v” may be any positive integer.

The waste fermentation system 14 includes a number, w, of sensors 122₁-122 _(w) operable to sense one or more physical operating conditionsof the waste fermentation system 14, and to supply such sensoryinformation to the PLC circuit 120 via corresponding signal paths 124₁-124 _(w), wherein “w” may be any positive integer. The PLC circuit 120is, in turn, operable to process the sensory data provided by the one ormore sensors 122 ₁-122 _(w) and produce one or more resulting analogactuator signals, which are then provided via signal paths 130 ₁-130_(x) to corresponding actuators associated with the waste fermentationsystem 14 to effectuate control of the fermentation process within thewaste fermentation system 14 wherein “x” may be any positive integer.

The residual liquid processing unit 16 includes a number, y, of sensors142 ₁-142 _(y) operable to sense one or more physical operatingconditions of the residual liquid processing unit 16, and to supply suchsensory information to the PLC circuit 140 via corresponding signalpaths 144 ₁-144 _(y), wherein “y” may be any positive integer. The PLCcircuit 140 is, in turn, operable to process the sensory data providedby the one or more sensors 142 ₁-142 _(y) and produce one or moreresulting analog actuator signals, which are then provided via signalpaths 150 ₁-150 _(z) to corresponding actuators associated with theexcess nutrient precipitation unit 16 to effectuate control of theexcess nutrient precipitation process within unit 16, wherein “z” may beany positive integer.

In an alternate embodiment, the PLC circuits 102, 120 and 140 may eachbe configured to include a number of analog-to-digital and a number ofdigital-to-analog converters. In this embodiment, a system controller100, as illustrated in phantom in FIG. 1, is operable to control theoperation of the biomaterial waste processing system 10. The systemcontroller 100 in this alternate embodiment is microprocessor-based, andincludes a memory 105 having stored therein a number of software controlalgorithms, wherein the microprocessor portion of the system controller100 is configured to execute such software algorithms to controloperation of the biomaterial waste processing system 10. The systemcontroller 100 includes a number of digital inputs and outputs (I/O)each electrically connected to corresponding I/Os of any number ofprogrammable logic controllers; e.g., PLCs 102, 120 and 140. The PLCcircuits 102, 120 and 140, in this embodiment, are configured todigitize analog signals provided by sensors associated with thebiomaterial waste processing system 10 to the system controller 100, andto convert digital output signals from the system controller 100 tocorresponding analog control signals for controlling actuatorsassociated with the biomaterial waste processing system 10.

In the embodiment illustrated in phantom in FIG. 1, the waste streampre-treatment system 12 includes a number, u, of sensors 104 ₁-104 _(u)operable to sense a corresponding number of physical operatingconditions of the various components 18, 30 and 38 of the waste streampretreatment system 12, and to supply such sensory information in theform of analog sensor signals to corresponding sensor inputs of the PLCcircuit 102 via corresponding signal paths 106 ₁-106 _(u), wherein “u”may be any positive integer. In embodiments of system 10 wherein theliquefied waste source 20 is a liquefied waste storage arrangement, suchas a liquefied waste storage lagoon, the liquefied waste source 20includes a level sensor 114 operable to sense the level of liquefiedwaste in the liquefied waste source 20, and to supply this sensoryinformation in the form of another analog sensor signal to PLC circuit102 via signal path 118. The PLC circuit 102 is, in turn, operableconvert the analog sensor signals to corresponding digital signals, andto supply the converted digital signals to the system controller 100 viasignal paths 108 ₁-108 _(u) and signal path 118. The system controller100 is operable, in this embodiment, to process the sensory dataprovided by the number of sensors 104 ₁-104 _(u) and 114, and producecorresponding digital actuator signals on any of a number, v, of signalpaths 110 ₁-110_(v), wherein “v” may be any positive integer. Thedigital actuator signals are converted by the PLC circuit 102 tocorresponding analog actuator signals, which are then provided viasignal paths 112 ₁-112 _(v) to corresponding actuators associated withthe various components 18, 30 and 38 of the waste stream pre-treatmentsystem 12 to effectuate control of the various components 18, 30 and 38.

The waste fermentation system 14 further includes a number, w, ofsensors 122 ₁-122 _(w) operable to sense one or more physical operatingconditions of the waste fermentation system 14, and to supply suchsensory information to the PLC circuit 120 via corresponding signalpaths 124 ₁-124 _(w), wherein “w” may be any positive integer. The PLCcircuit 120 is, in turn, operable to supply the sensory information tothe system controller 100 via signal paths 126 ₁-126 _(w). PLC circuit120 may include any number of PLC subcircuits and is in any caseoperable to convert the analog sensor data to one or more digitalsignals, and to supply the converted signals to the system controller100. The system controller 100 is operable, in this embodiment, toprocess the sensory data provided by the one or more sensors 122 ₁-122_(w) and produce one or more resulting digital actuator signals on anumber, x, of signal paths 128 ₁-128 _(x), wherein “x” may be anypositive integer. The one or more corresponding digital actuator signalsare converted by the PLC circuit 120 to corresponding analog actuatorsignals, which are then provided via signal paths 130 ₁-130 _(x) tocorresponding actuators associated with the waste fermentation system 14to effectuate control of the fermentation process within the wastefermentation system 14.

The residual liquid post-processing system 16 includes a number, y, ofsensors 142 ₁-142 _(y) operable to sense one or more physical operatingconditions of the excess nutrient precipitation unit 80, and to supplysuch sensory information to the PLC circuit 140 via corresponding signalpaths 144 ₁-144 _(y), wherein “y” may be any positive integer. The PLCcircuit 140 is, in turn, operable to supply the sensory information tothe system controller 100 via signal paths 146 ₁-146 _(y). PLC circuit140 may include any number of PLC subcircuits and is in any caseoperable to convert the analog sensor data to one or more digitalsignals, and to supply the converted signals to the system controller100. The system controller 100 is operable, in this embodiment, toprocess the sensory data provided by the one or more sensors 142 ₁-142_(y) and produce one or more resulting digital actuator signals on anumber, z, of signal paths 148 ₁-148 _(z), wherein “z” may be anypositive integer. The one or more corresponding digital actuator signalsare converted by the PLC circuit 140 to corresponding analog actuatorsignals, which are then provided via signal paths 150 ₁-150 _(z) tocorresponding actuators associated with the excess nutrientprecipitation unit 16 to effectuate control of the excess nutrientprecipitation process within unit 16.

For ease of illustration and description, electronic control of thevarious components of the biomaterial waste processing system 10 will bedescribed herein as being accomplished via the three illustrated PLCcircuits 102, 120 and 140, it being understood that alternate forms ofsuch control may alternatively or additionally be implemented.

Referring now to FIGS. 2A and 2B, front and side elevational viewsrespectively of one illustrative embodiment of the sand separation unit18 forming part of the waste stream pre-treatment system 12 is shown. Itwill be appreciated that some of the details illustrated in FIG. 2A arenot duplicated in FIG. 2B for brevity and ease of illustration. In theillustrated embodiment, the sand separation unit 10 includes a firstseparation tank 160 and a second separation tank 162 elevated above theground or other support structure by support frame 164. The liquefiedwaste supplied by the liquefied waste source 20 via conduit 22 entersliquefied waste inlets 166 and 168 of tanks 160 and 162 respectively,wherein the inlets 166 and 168 are each positioned adjacent to the topsof tanks 160 and 162. At the bottom of tanks 160 and 162, sand outlets170 and 172 respectively are defined, and liquefied waste outlets aredefined through lower portions of the sidewalls of the tanks 160 and162. Only one liquefied waste outlet 174A (of tank 160) is shown in theside elevational view of unit 18 in FIG. 2B, although it will beunderstood that tank 162 defines an identically positioned liquefiedwaste outlet.

The sand outlet 170 of the sand separation tank 160 is connected via asand conduit 176 to a sand inlet 178 defined through the top of a sandcollection tank 180 positioned below each of the sand separation tanks160 and 162. The sand outlet 172 of the sand separation tank 162 islikewise connected via a sand conduit 182 to another sand inlet 184defined through the top of the sand collection tank 180. Sand extractionvalves 186 and 188 provide selective control of sand flow through sandconduits 176 and 182 respectively. The sand collection tank 180 issupported above the ground or other support structure by a support frame190, and the bottom of the sand collection tank 180 defines a sandoutlet 192 fluidly coupled to a sand inlet 195 of a sand transportdevice 196 via a sand conduit structure 194. In the illustratedembodiment, the sand transport device 196 is a conventional 45-degreeelongated auger defining an auger outlet 198 near an end opposite thesand inlet port 195, wherein the auger 196 is operable in a known mannerto receive sand expelled from the sand outlet 192 of the sand collectiontank 180 via the sand conduit structure 194, and to transport the sandto the opposite end 198 of the sand extraction auger 196 where it may becollected and stored and/or transported to a convenient location usingconventional machinery. Alternatively, the sand transport device 196 maybe provided in the form of an auger positioned other than 45 degreesrelative to unit 18 (or relative to the ground or other support surfacesupporting unit 18), a conventional sand conveyor, or the like.

Adjacent to the tops of the sand separation tanks 160 and 162 a supportframe 200 supports a number of rotational auger motors 202, 218 and 222.Auger motor 202 is rotatably coupled to an auger shaft 204 extendinginto the sand separation tank 160. Adjacent to the interface between thecylindrical and conical portions of tank 160, a bar or rod 208 extendslaterally away from auger shaft 204, which is connected adjacent freeends thereof to angled support bars or rods 210A and 210B extendinggenerally upwardly toward, and connected to, the auger shaft 204. Theopposite ends of bar or rod 208 carry upwardly extending plates 212A and212B positioned adjacent the sidewalls of the tank 160, and theliquefied waste outlet 174A defined through the sidewall of the tank 160is positioned between the bar or rod 208 and the tops of plates 212A and212B. Another bar or rod 214 is affixed to a bottom end of the augershaft 204, and opposite ends of the bar or rod 214 are connected toangled bars or rods 216A and 216B extending downwardly from oppositeends respectively of bar or rod 208 toward the bottom of the conicaltank bottom. The ends of the angled bars or rods 216A and 216B at thebottom of the conical tank bottom are connected together. Between theangled support bars or rods 210A and 210B and the top of the tank 160, anumber of mixing tines 206 extend transversely from the auger shaft 206.The auger shaft 204 and structures 206-216B extending from the augershaft 204 define a first sand separation auger 205 rotatable within thesand separation tank 160 to separate sand from the liquefied wasteentering the sand separation unit 18.

Auger motor 218 is rotatably coupled to an auger shaft 220 extendinginto the sand separation tank 162, and an auger structure identical tothat just described with respect to the sand separation tank 160 extendsfrom auger shaft 220 to define a second sand separation auger 215. Thestructures of the sand separation tanks 160 and 162, and of the sandseparation augers 205 and 215, are configured to create a lateral flowof the liquefied waste about the tanks 160 and 162 when the augers 205and 215 are rotatably driven while sand resident in the liquefied wastematter extracted from the liquefied waste source 20 drops out of theremaining liquefied waste and collects in the conical bottom portion ofthe sand separation tanks 160 and 162.

The auger motor 222 is rotatably coupled to an auger shaft 224 extendinginto the sand collection tank 160. Adjacent to the interface between thecylindrical and conical portions of the tank 160, a pair of bars or rods226A and 226B extend laterally away from the auger shaft 224 in oppositedirections, which are connected adjacent free ends thereof to ends ofangled bars or rods 232A and 2132B extending generally downwardly towardthe bottom of the conical bottom portion of the sand collection tank180. The ends of bars or rods 226A and 226B adjacent to the sidewalls ofthe tank 180 carry upwardly extending plates 228A and 228B. Another baror rod 230 is affixed to a bottom end of the auger shaft 224, andopposite ends of the bar or rod 230 are connected to angled bars or rods232A and 232B extending downwardly toward the bottom of the conicalportion of the tank 180. The ends of the angled bars or rods 232A and232B at the bottom of the conical tank bottom are connected together viaanother bar or rod 234. The auger shaft 224 and structures 226A-234extending from the auger shaft 224 define a sand extraction auger 225rotatable within the sand collection tank 180 to agitate the sandcollected from the sand separation tanks 160 and 162 and expel thecollected sand from the sand collection tank 180. A water inlet 236 isdefined through the sidewall of the sand collection tank 180 adjacent tothe bottom of conical bottom portion of the tank 180.

Referring now to FIG. 3, a schematic diagram of one illustrativeembodiment of a control system for controlling the sand separation unit18 of FIGS. 1-2B is shown. In the illustrated embodiment, the liquidwaste inlet, LWI, of the sand separation unit 18 is fluidly connected toa pair of liquefied waste pumps 250 and 252. Pump 250 is electricallyconnected to a conventional pump driver 254 that is electricallyconnected to an actuator control output of PLC circuit 102 via signalpath 112 ₀, and pump 252 is likewise electrically connected to aconventional pump driver 256 that is electrically connected to anactuator control output of PLC circuit 102 via signal path 112 ₁. Theoutlets of pumps 250 and 252 are each passed through mechanicalbutterfly and check valves BV and CV respectively, and are fluidlycoupled to the liquefied waste inlets 166 and 168 of the sand separationtanks 160 and 162 respectively via conduits 258 and 260 respectively. Inthe illustrated embodiment, the pumps 250 and 252 are sized, as are thepump drivers 254 and 256, to provide for the pumping of liquefied wastefrom the liquefied waste source at a predefined liquefied waste flowrate; e.g., 100 gallons (379 liters) per minute (gpm) (lpm). Overworkingof the pumps 250 and 252 is avoided by alternately activating each pump250 and 252 for a predefined time period while the other is deactivated,thereby allowing for periodic cooling of the pumps 250 and 252 and pumpdrivers 254 and 256. It will be understood, however, that the pumps 250and 252 and pump drivers 254 and 256 may alternatively be replaced witha single pump and single pump driver sized for continuous operation toat the predefined liquefied waste flow rate. In either case, acontinuous flow of liquefied waste at the predefined liquefied wasteflow rate is supplied to conduits 258 and 260.

A liquefied waste inlet valve 262 is disposed in-line with conduit 258,and is electrically connected to an actuator output of PLC circuit 102via signal path 112 ₂. Likewise another liquefied waste inlet valve 264is disposed in-line with conduit 260, and is electrically connected toanother actuator output of PLC circuit 102 via signal path 112 ₃. Theliquefied waste inlet valves 262 and 264 are controlled to selectivelydirect the liquefied waste provided by pumps 250 and 252 to the sandseparation tanks 160 and 162.

The liquefied waste outlet 174A of the sand separation tank 160 ispassed through a butterfly valve, BV, and fluidly connected to theliquefied waste outlet, LWO, of the sand separation unit 18 via conduit266. A liquefied waste outlet valve 268 is disposed in-line with conduit266, and is electrically connected to an actuator output of PLC circuit102 via signal path 112 ₄. The liquefied waste outlet 174B of the sandseparation tank 162 is also passed through a butterfly valve, BV, and isfluidly connected to conduit 266, downstream of the liquefied wasteoutlet valve 268, via conduit 270. Another liquefied waste outlet valve272 is disposed in-line with conduit 270, and is electrically connectedto another actuator output of PLC circuit 102 via signal path 112 ₅. Yetanother liquefied waste outlet valve 274 is disposed in-line withconduit 266, downstream of valve 268 and of the junction of conduit 270with conduit 266, and is electrically connected to yet another actuatoroutput of PLC 102 via signal path 112 ₆. Conduit 266 is fluidlyconnected to conduit 32 supplying liquefied waste to the liquid/solidseparation unit 30. The liquefied waste control valves 268, 272 and 274are controlled to selectively extract liquefied waste from the sandseparation tanks 160 and 162.

The sand extraction valve 186 disposed in-line with sand extractionconduit 176 is electrically connected to an actuator output of PLCcircuit 102 via signal path 112 ₇, and the sand extraction valve 188disposed in-line with sand extraction conduit 182 is electricallyconnected to another actuator output of PLC circuit 102 via signal path112 ₈. An overflow conduit 276A is fluidly connected at one end to thesand extraction conduit 176 between the sand extraction valve 186 andthe sand inlet 178 of the sand collection tank 180, and another overflowconduit 276B is fluidly connected at one end to the sand extractionconduit 182 between the sand extraction valve 188 and the sand inlet 184of the sand collection tank 180. The opposite ends of overflow conduits276A and 276B are both fluidly connected to another overflow conduit278A fluidly connected to an overflow inlet of the sand separation tank160, and to yet another overflow conduit 278B fluidly connected to anoverflow inlet of the sand separation tank 162. The sand extractionvalves 186 and 188 are controlled to selectively extract sand from thesand separation tanks 160 and 162 and collect the extracted sand in thesand collection tank.

The water inlet, WI, of the sand separation unit 18 is fluidly connectedto the water inlet 236 of the sand collection tank 180 via a waterconduit 280, wherein conduit 280 is fluidly connected to water inletconduit 26. A water inlet valve 282 is disposed in-line with conduit280, and is electrically connected to an actuator output of the PLCcircuit 102 via signal path 112 ₉. The water inlet valve 282 iscontrolled to selectively supply water to the sand collection tank 180.

The control system illustrated in FIG. 3 also includes a number ofsensors producing sensory information relating to operation of the sandseparation unit 18. For example, a pressure sensor 104 ₁ is fluidlycoupled to the sand separation tank 160, and is electrically connectedto a sensor input of the PLC circuit 102 via signal path 106 ₁. Anotherpressure sensor 104 ₂ is fluidly coupled to the sand separation tank162, and is electrically connected to another sensor input of the PLCcircuit 102 via signal path 106 ₂. The pressure sensors 104 ₁ and 104 ₂provide the PLC circuit 102 with information relating to the pressureswithin the sand separation tanks 160 and 162 respectively, and the PLCcircuit 102 is operable in a known manner to process this pressureinformation and determine the levels of liquid or liquefied matterwithin the separation tanks 160 and 162 respectively. Alternatively,each tank 160 and 162 may include one or more other conventional levelsensors configured to provide the PLC circuit 102 with informationrelating to one or more liquid or liquefied matter thresholds withintanks 160 and 162. In any case, a conventional flow meter or flow sensor104 ₃ is disposed in-line with the liquefied waste outlet conduit 266downstream of the liquefied waste control valve 268 and of the junctionof conduit 270 with conduit 268, and upstream of the liquefied wastecontrol valve 274, and is electrically connected to another sensor inputof the PLC circuit 102 via signal path 106 ₃. The PLC circuit 102 isresponsive to the sensory information provided by sensors 104 ₁-104 ₃ tocontrol one or more operational features of the sand separation unit 18.

The auger motor 202 is electrically connected to an auger driver 284that is electrically connected to another actuator output of the PLC 102via signal path 112 ₁₀, and also electrically connected to a sensorinput of the PLC circuit 102 via signal path 106 ₄. The auger driver 284is responsive to an actuator control signal supplied by the PLC 102 todrive auger motor 202, and the auger driver 284 and/or auger motor 202further includes a “sensor” for determining and monitoring the operatingtorque of the auger motor 202. Such a “sensor” may be a conventionalstrain-gauge type torque sensor operatively coupled to a rotating driveshaft of the auger motor 202 and operable to produce a sensor signalcorresponding to the operating torque of the auger motor 202, or mayalternatively be a so-called virtual sensor implemented in the form ofone or more software algorithms resident within the PLC circuit 102 andresponsive to one or more measurable operating parameters associatedwith the auger driver 284 and/or auger motor 202 to derive or infer theoperating torque value. For example, the auger driver 284 may include acurrent sensor producing a current sensor signal indicative of drivecurrent being drawn by the driver 284, and/or the auger motor 202 mayinclude a position and/or speed sensor producing a signal correspondingto the rotational speed and/or position of the auger shaft 204. The PLCcircuit 102 may be responsive to any such sensor signals, and/or toother information relating to the operation of the auger driver 284and/or auger motor 202, to estimate the operating torque of the augermotor 202 as a known function thereof. In any case, the signal path 106₄ carries one or more torque feedback signals to the PLC circuit 102from which the operating torque of the auger motor 202 may be determineddirectly or estimated.

The auger motor 218 is likewise electrically connected to an augerdriver 286 that is electrically connected to another actuator output ofthe PLC 102 via signal path 112 ₁₁, and also electrically connected toanother sensor input of the PLC circuit 102 via signal path 106 ₅. Theauger driver 284 is responsive to an actuator control signal supplied bythe PLC 102 on signal path 112 ₁₁ to drive auger motor 218, and toprovide a torque feedback signal to the PLC circuit 102, using any ofthe techniques just described, corresponding to the operating torque ofthe auger motor 218 or from which the operating torque of the augermotor 218 may be estimated.

The auger motor 222 is also electrically connected to an auger driver288 that is electrically connected to another actuator output of the PLC102 via signal path 112 ₁₂, and also electrically connected to anothersensor input of the PLC circuit 102 via signal path 106 ₆. The augerdriver 288 is responsive to an actuator control signal supplied by thePLC 102 on signal path 112 ₁₂ to drive auger motor 222, and to provide atorque feedback signal to the PLC circuit 102, using any of thetechniques described hereinabove, corresponding to the operating torqueof the auger motor 222 or from which the operating torque of the augermotor 222 may be estimated.

The sand extraction auger 196 also includes an auger motor electricallyconnected to an auger driver 290 that is electrically connected toanother actuator output of the PLC 102 via signal path 112 ₁₃, and alsoelectrically connected to another sensor input of the PLC circuit 102via signal path 106 ₇. The auger driver 290 is responsive to an actuatorcontrol signal supplied by the PLC 102 on signal path 112 ₁₃ to drivethe motor of the sand extraction auger 196, and to provide a torquefeedback signal to the PLC circuit 102, using any of the techniquesdescribed hereinabove, corresponding to the operating torque of theauger 196 or from which the operating torque of the auger 196 may beestimated. The sand outlet of the sand collection tank 180 is fluidlycoupled to the sand inlet of the sand extraction auger 196 via conduitstructure 194. The outlet 198 of the sand extraction auger 196 definesthe sand output, SNDO, of the sand separation unit 18 and is fluidlycoupled to the sand extraction conduit 28 via conduit 292.

Referring now to FIGS. 4A and 4B, a flowchart of one illustrativeembodiment of a software control algorithm 300 for controlling the sandseparation unit 18 via the control system of FIG. 3 is shown. Controlalgorithm 300 is stored within, or programmed into, the PLC circuit 102,and the PLC circuit 102 is operable to execute algorithm 300 to controlthe operation of the sand separation unit 18. The control algorithm 300includes a number of different and independently executing controlroutines, and each of these different control routines will be describedseparately. Throughout each of the different control routines of controlalgorithm 300, it will be understood that the PLC circuit 102 isoperable to continually operate the sand separation augers 205 and 215,as well as the sand extraction auger 225. In any case, the controlalgorithm 300 includes a first control routine 302 for controlling theoperation of the liquefied waste pumps 250 and 252, and routine 302begins at step 304 where the PLC circuit 102 is operable to determinethe level, L1, of the liquefied waste in the liquefied waste source. Inthe illustrated embodiment of the system 10 of FIG. 1, the PLC circuit102 is operable to execute step 304 by monitoring the output of thelevel sensor 114. Following step 304, the PLC circuit 102 is operable atstep 306 to compare L1 to a threshold level value, L1 _(TH), wherein L1_(TH) corresponds to a minimum allowable level of liquefied waste in theliquefied waste source 20. If the PLC circuit 102 determines at step 306that L1 is less than or equal to L1 _(TH), execution of the controlroutine 302 loops back to step 304 with no further action. If, however,the PLC circuit 102 determines at step 306 that L1 is greater than L1_(TH), execution of the control routine 302 advances to step 308 wherethe PLC circuit 102 is operable as described hereinabove to control thewaste inlet pumps to direct liquefied waste from the liquefied wastesource 20 to the sand separation tanks 160 and 162.

From step 308, execution of the control routine 302 loops back to step304. The control routine 302 is thus operable to control the waste inletpumps 250 and 252 to provide liquefied waste to the sand separationsystem 18 only as long as the liquefied waste source 20 has storedtherein a sufficient quantity of liquefied waste. It will be understoodthat in embodiments of the biomaterial waste processing system 10wherein the liquefied waste source is another waste processing system,the control routine 302 may be omitted, or may instead be modified tooperate pumps 250 and 252 only when such a waste processing system issupplying a sufficient quantity of liquefied waste. Any suchmodifications to the control routine 302 would be a mechanical step fora skilled artisan.

The sand separation unit control algorithm 300 includes another controlroutine 310 for controlling the filling and emptying of the sandseparation tanks 160 and 162. Control routine 310 begins at step 312where the PLC circuit 102 is operable to control opening and closing ofthe liquefied waste inlet valves 262 and 264 to direct the flow ofliquefied waste provided by pumps 250 and 252 to one of the sandseparation tanks 160, 162 while the other tank 160, 162 is beingemptied. Thereafter at step 314, the PLC circuit 102 is operable todetermine the level, L2, of liquefied waste in the sand separation tank160, 162 that is being filled as a result of step 312. In theillustrated embodiment of the system 10 of FIG. 1, the PLC circuit 102is operable to execute step 314 by monitoring the output of anappropriate one of the pressure sensors 104 ₁ and 104 ₂, and determiningthe level of liquefied waste in the corresponding tank as a knownfunction of the pressure signal. Following step 314, the PLC circuit 102is operable at step 316 to compare L2 to a high threshold level value,L2 _(HTH), wherein L2 _(HTH) corresponds to a maximum allowable level ofliquefied waste in either tank 160 or 162. If the PLC circuit 102determines at step 316 that L2 is less than L2 _(HTH), execution of thecontrol routine 310 loops back to step 314 with no further action. If,however, the PLC circuit 102 determines at step 316 that L2 is greaterthan or equal to L2 _(HTH), indicating that the filling sand separationtank 160 or 162 is now full, execution of the control routine 310advances to each of a number of control branches. For example, the “yes”branch of step 316 advances to step 318 where the PLC circuit 102 isoperable to control opening and closing of the liquefied waste inletvalves 262 and 264 to direct the flow of liquefied waste provided bypumps 250 and 252 to the opposite (now empty) sand separation tank 160,162 to commence filling that tank. Execution of the control routine 310loops from step 318 back to step 314 to monitor the level, L2, of thesand separation tank 160, 162 now being filled as a result of step 318.

The “yes” branch of step 316 also advances to step 320 where the PLCcircuit 102 is operable to open the liquefied waste outlet valve 268,272 of the now filled sand separation tank 160, 162. While the sandseparation tank 160, 162 was being filled with liquefied waste via steps312-316, the corresponding sand separation auger 205, 215 wascontinuously rotating to create a lateral flow of the liquefied wasteabout the sand separation tank 160, 162 to thereby suspend the wastesolids in the circulating fluid while the sand in the tank 160, 162dropped out of the lateral flow and was collected in the bottom of thetank 160, 162. By the time the sand separation tank 160, 162 is filledat step 316, a substantial amount of the sand present in the tank160,162 will have dropped out of the lateral flow, and the resultingliquefied waste may begun to be removed at step 320 by opening acorresponding liquefied waste outlet valve 268, 272. Following step 320,the PLC circuit 102 is operable at step 322 to monitor the flow rate,FR, of the liquefied waste exiting the sand separation unit 18 viaconduit 266. In the illustrated embodiment, the PLC circuit 102 isoperable to execute step 322 by monitoring the flow signal produced bythe flow meter 104 ₃. Thereafter at step 324, the PLC circuit 102 isoperable to adjust or modulate the opening of the liquefied waste outletvalve 268, 270 so that the flow rate, FR, of the liquefied waste out ofthe sand separation tank 160, 162 is maintained near a target flow rate,FRT; e.g., 100 gpm.

Following step 324, the PLC circuit 102 is operable at step 326 tomonitor the level, L2, of liquefied waste in the sand separation tank160, 162 from which the liquefied waste is being removed. Thereafter atstep 328 the PLC circuit 102 is operable to compare L2 to a lowthreshold level; L2 _(LTH), wherein L2 _(LTH) corresponds in theillustrated embodiment to a level at which the liquefied waste may beconsidered to have been substantially removed from the sand separationtank 160, 162. If, at step 328, the PLC circuit 102 determines that L2is greater than L2 _(LTH), execution of the control routine 310 loopsback to step 326. If, on the other hand, the PLC circuit 102 determinesat step 328 that L2 is less than or equal to L2 _(LTH), the liquefiedwaste is considered to have been sufficiently removed from the sandseparation tank 160, 162 and the PLC circuit 102 is operable thereafterat step 330 to close the waste outlet valve 268, 272 of the now emptiedsand separation tank 160, 162. Execution of the control routine 310loops from step 330 back to step 314.

The “yes” branch of step 316 also advances to step 332 where the PLCcircuit 102 is operable to open the water supply valve 282 to the sandcollection tank 180 for a predefined time period, T1. In the illustratedembodiment, T1 is selected such that water entering the sand collectiontank 180 will fill the sand collection tank 180 and travel up the sandextraction conduit 176, 182 up to the outlet of the sand extractionvalve 186, 188. Any excess water flows up the overflow conduits 276A,276B and 278A, 278B, and is spilled into the sand separation tank 160,162. Step 332 is included within the control routine 310 to provide aflow medium within the sand extraction conduit 176, 182 between the sandcollection tank 180 and the sand extraction valve 186, 188 to facilitatethe transfer of sand from the sand separation tank 160, 162 into thesand collection tank 180 via control of the sand extraction valve 186,188. Following step 332, the PLC circuit 102 is operable at step 334 toopen the sand extraction valve 186, 188 between the now emptying sandseparation tank 160, 162 and the sand collection tank 180 to allow sandcollected in the bottom of the sand separation tank 160, 162 to flowthrough the sand extraction conduit 176, 182 and into the sandcollection tank 180.

Following step 334, the PLC circuit 102 is operable at step 336 todetermine the operating torque, TQ_(SSA), of the sand separation auger205, 215 of the sand separation tank 160, 162 being emptied. In theillustrated embodiment, the PLC circuit 102 is operable to execute step336 using any of the feedback torque monitoring techniques describedhereinabove. Following step 336, the PLC circuit 102 is operable at step338 to compare the operating torque, TQ_(SSA), of the auger 205, 215 toa torque threshold, TQ_(TH1). As sand is transferred from the sandseparation tank 160, 162 to the sand collection tank 180, the operatingtorque of the sand separation auger 205, 215 will decrease due to thediminishing sand quantity in the bottom of the sand separation tank 160,162. The torque threshold TQ_(TH1) corresponds to an operating torque ofthe sand separation auger 205, 215 below which the sand separation tank160, 162 may be considered to be sufficiently emptied of sand. Thus, ifthe PLC circuit 102 determines at step 338 that TQ_(SSA) is greater thanor equal to TQ_(TH1), the sand separation tank 160, 162 still holds aquantity of sand that may be removed, and execution of the controlroutine 310 thus loops back to step 336. If, on the other hand, the PLCcircuit 102 determines at step 338 that TQ_(SSA) is less than TQ_(TH1),enough sand has been extracted from the sand separation tank 160, 162 toconsider it emptied of sand, and execution of the control routine 310advances to step 340 where the PLC circuit 102 is operable to close thesand extraction valve 176, 182. From step 340, execution of the controlroutine 310 loops back to step 314 where the PLC circuit 102 is operableto monitor the liquefied waste level of the opposite sand separationtank 160, 162 now being filled.

The sand separation unit control algorithm 300 further includes anothercontrol routine 342 for controlling emptying of the sand collection tank180. Control routine 342 begins at step 344 where the PLC circuit 102 isoperable to determine the operating torque, TQ_(SCA), of the sandcollection auger 225 rotating within the sand collection tank 180. Inthe illustrated embodiment, the PLC circuit 102 is operable to executestep 344 using any of the feedback torque monitoring techniquesdescribed hereinabove. Following step 344, the PLC circuit 102 isoperable at step 346 to compare the operating torque, TQ_(SCA), of theauger 225 to a torque threshold, TQ_(TH2). As sand is transferred fromthe sand separation tanks 160 and 162 to the sand collection tank 180,the operating torque of the sand collection auger 225 will increase dueto the increasing sand quantity in the sand collection tank 180. Thetorque threshold TQ_(TH2) corresponds to an operating torque of the sandcollection auger 225 above which the sand collection tank 180 may beconsidered to have a quantity of sand collected therein that meritsremoval. Thus, if the PLC circuit 102 determines at step 346 thatTQ_(SCA) is less than or equal to TQ_(TH2), the sand collection tank 180does not hold a sufficient quantity of sand that merits removal, andexecution of the control routine 342 thus loops back to step 344. If, onthe other hand, the PLC circuit 102 determines at step 344 that TQ_(SCA)is greater than TQ_(TH2), the sand collection tank 180 holds asufficient quantity of sand to merit removal of the collected sand, andexecution of the control routine 342 advances to step 348 where the PLCcircuit 102 is operable to activate the sand extraction auger 196. Withthe sand collection auger 180 constantly rotating, activation of thesand extraction auger 196 at step 348 will cause sand collected in thesand collection tank 180 to flow out of the sand outlet 192 and throughthe conduit structure 194 into the sand inlet 195 of the sand extractionauger. Operation of the sand extraction auger 196 transfers the sandfrom the sand inlet 195 to the sand outlet 198 of the auger 196, wherethe extracted sand may be stored and/or transported via conventionalmachinery to a convenient location.

Following step 348, the PLC circuit 102 is operable at step 350 to againdetermine the operating torque, TQ_(SCA), of the sand collection auger225 rotating within the sand collection tank 180, and to also determinethe operating torque, TQ_(SEA), of the sand extraction auger 196, usingany of the feedback torque monitoring techniques described hereinabove.Thereafter at step 352, the PLC circuit 102 is operable to compareTQ_(SEA) to a torque threshold value, TQ_(TH3), and to compare thechange in TQ_(SCA) to another torque threshold value, TQ_(TH4). Thetorque thresholds TQ_(TH3) and TQ_(TH4) are selected to allow detectionof whether sand contained within the sand collection tank 180 issufficiently loose to allow it to be extracted from the sand collectiontank 180. In this regard, the PLC circuit 102 is operable at step 352 todetermine whether the operating torque, TQ_(SEA), of the sand extractionauger 196 has dropped below TQ_(TH3) while the change in the operatingtorque, ΔTQ_(SCA), of the sand collection auger 225 over a recent timeinterval is less than TQ_(TH4). If so, this indicates that the sandwithin the sand collection tank 180 has become too tightly packed, andrehydration of is necessary to facilitate extraction of the sand fromthe sand collection tank 180. In this case, execution of the controlroutine 342 advances to step 354 where the PLC circuit 102 is operableto open the water supply valve 282 for a time period T2 to supply waterfrom the water source 24 to the sand collection tank 180. The timeperiod T2 is selected to allow sufficient rehydration of the sand withinthe sand collection chamber 180 so that it may be subsequently removedvia the sand removal valve 194 and sand extraction auger 196. If,however, the PLC circuit 102 determines at step 352 that TQ_(SEA) isgreater than or equal to TQ_(TH3), and/or ΔTQ_(SCA) is greater than orequal to TQ_(TH4), this indicates that the sand within the sandcollection tank 180 is sufficiently hydrated to allow extraction thereofvia the sand removal valve 194 and sand extraction auger 196.

Execution of the control routine 342 advances from the “no” branch ofstep 352 and from step 354 to step 356 where the PLC circuit 102 isoperable to compare the operating torque, TQ_(SEA), of the sandextraction auger 196 to another torque threshold value, TQ_(TH5). Thetorque threshold, TQ_(TH5), is set to an operating torque value belowwhich the sand extraction auger 196 is not transferring a sufficientquantity of sand to warrant operation of the sand extraction auger 196.Thus, if the PLC circuit 102 determines at step 356 that TQ_(SEA) isgreater than or equal to TQ_(TH5), execution of the control routine 342loops back to step 350. If, on the other hand, the PLC circuit 102determines at step 356 that TQ_(SEA) is less than TQ_(TH5), execution ofthe control routine 342 advances to step 358 where the PLC circuit 102is operable to deactivate the sand extraction auger 196. Thereafter,execution of the control routine 342 loops back to step 344.

For continuous flow operation of the sand separation unit 18, controlroutine 310 is coordinated in the timing of its various executionbranches so that one sand separation tank 160 or 162 is being filledwith liquefied waste according to steps 312-318 while the other sandseparation tank 160 or 162 is being simultaneously emptied of liquefiedwaste and sand according to steps 320-340. In such a continuous flowsystem, steps 318, 330 and 340 thus loop directly back to step 314 ofcontrol routine 310. For non-continuous flow operation, control routine310 may require one or more delay steps to coordinate the filling of onesand separation tank 160 or 162 with the emptying of the other sandseparation tank 160 or 162, and/or control algorithm 300 may require anadditional control routine to control the feed rate of the liquefiedwaste from the liquefied waste source 20 to the sand separation tanks160 and 162. In either case, control routine 342 operates independentlyof control routine 310 such that sand is extracted from the sandcollection tank 180 only when the operating torque of the sandcollection auger 225 exceeds a specified torque threshold.

Referring now to FIGS. 5A and 5B, side and front elevational viewsrespectively of one illustrative embodiment of the liquid/solidseparation unit 30 forming part of the waste stream pre-treatment system12 is shown. In the illustrated embodiment, the liquid/solid separationunit 30 includes a screen shaker in the form of a shaker table 360having a liquefied waste inlet 362 configured to receive liquefied wastefrom the sand separation unit 18 and supply the liquefied waste throughthe top of the shaker table 360 to an interior of the table 360. Theshaker table 362 includes a conventional screen, mesh fabric or the like(not shown) positioned over a liquid waste outlet 364 and configured totrap waste solid waste particles larger than a predefined particle sizewhile allowing liquid waste and solid waste particles smaller than thepredefined particle size to pass through the screen or mesh to a smallparticle extraction unit 366 via the liquid waste outlet 364. The shakertable 362 also has a large waste particle outlet 368 coupled to thelarge waste particle outlet conduit 36. In one illustrative embodiment,the screen or mesh is configured to trap waste and other particles;e.g., straw, hay, bedding and the like, that are approximately 20microns and larger, while passing liquid waste and waste particles lessthan 20 microns in size to the liquid waste outlet 364. It will beunderstood, however, that the screen or mesh may be configured to trapwaste particles having any desired minimum size without detracting fromthe scope of the claims appended hereto. In any case, a conventionalconveyor system 370 or other conventional transport device is positionedbeneath the large waste particle outlet conduit 36, and is configured toreceive large waste particles, LWP, removed from the shaker table 360via conduit 36, and to transport the removed large waste particles to aconvenient location for storage, disposal or further processing.

In the illustrated embodiment, the shaker table 360 is movably connectedto a support frame 374 via four conventional shaker table supports372A-372D, although more or fewer such supports may alternatively beused. In any case, the liquid/solid separation system 30 includes anumber of shaker motors configured to shake, vibrate or otherwiserapidly move the shaker table relative to the support frame 374. In theillustrated embodiment, system 30 includes two such motors 376A and 376Bmounted to the table 360 at approximately a 45-degree angle relative toa longitudinal plane of the support frame 374. Thusly mounted, theshaker motors 376A and 376B are controlled to shake the shaker table 360in both the vertical and horizontal directions to cause the liquidportion and small particles carried by of the liquefied waste to passthrough the screen or mesh while the large waste particles carried bythe liquefied waste are trapped by the screen or mesh.

The shaker table 360 and support frame 374 are elevated above the smallparticle extraction unit 366 via another support frame 378 such that theliquid outlet 364 of the shaker table, which in the illustratedembodiment is defined centrally through the bottom of the shaker table360, extends into the top of the small particle extraction unit 366 thatis positioned under the shaker table 360.

Referring specifically to FIG. 5B, details relating to one illustrativeembodiment of the small particle extraction unit 366 are shown. In theembodiment shown in FIG. 5B, the large waste particle outlet 368, largewaste particle outlet conduit 36 and large waste particle transportdevice 370 have been omitted for ease of illustration and to moreclearly illustrate details of the small particle extraction unit 366. Inthe illustrated embodiment, the small particle extraction unit 366includes a first wall 380 extending from the top of the unit 366downwardly into the interior of the unit 366 adjacent to the liquidoutlet 364 of the shaker table 360. The first wall 380 is included inthe illustrated embodiment to confine the liquid waste entering thesmall particle extraction unit 366 between the outer wall 366A of theunit 366 and the first wall 380 so as to direct the entering liquidwaste to a small particle collection area 382A defined by the bottomfloor 366C of the unit 366. A small particle outlet 396 is definedthrough the small particle collection area 382A of the bottom or floor366C of the small particle extraction unit 366. An incline or ramp 384extends upwardly away from the small particle collection area 382Atoward an opposite wall 366B of the small particle extraction unit 366at a predefined angle relative to the bottom or floor 366C of the unit366; e.g., 15 degrees, and terminates at a second wall 386 extendingupwardly from the bottom floor 366C of the small particle extractionunit 366. A first spill plate 388A extends away from the top of thesecond wall 386 downwardly and toward the opposite wall 366B of thesmall particle collection unit 366, and a second spill plate 388Bextends away from the opposite wall 366B of the small particleextraction unit 366 below the first plate 386, and downwardly and towardthe second wall 386. The bottom of the small particle extraction tank366 between the second wall 386 and the opposite sidewall 366B defines aliquid waste collection area 382B having a liquid waste outlet 390coupled to a liquid waste extraction pump 392 via conduit 410. Attachedto the underside of the inclined or ramped floor 384 is a vibrator 394that may be selectively operated to urge small particles collected orsettled on the inclined or ramped floor 384 downwardly toward the smallparticle collection area 382A.

In the operation of the liquid/solid separation unit 30, the shakertable 360 receives liquefied waste via the liquefied waste inlet 362,and is controllably shaken to force the liquid waste and small wasteparticle portion downwardly toward the liquid waste outlet 364 whiletrapping the large waste particles carried by the liquefied waste anddirecting the collected large waste particles, LWP, toward the largewaste particle outlet, LPO, and onto the large waste particle transportdevice 370. The screen or mesh (not shown) will require periodicbackwashing with pressurized water to remove trapped large wasteparticles, and the shaker table accordingly includes a water inletalthough this is not specifically shown in FIGS. 5A and 5B. In any case,the liquid waste stream exiting the shaker table 360 via the liquidwaste outlet 364 enters the small particle extraction unit 366 and isconfined by walls 380 and 366A, which direct the liquid waste toward thesmall particle collection area 382A of the bottom or floor 366C of thesmall particle extraction unit 366. As more liquid waste enters thesmall particle extraction unit 366, it rises up the inclined or rampedfloor 384, up the vertical wall 386, and spills over plates 388A and388B into the liquid waste collection area 382B of the bottom or floorof the small particle extraction unit 366. The configuration of theinclined or ramped floor 384, vertical wall 386 and spill plate 388Acreates a very low liquid flow region, and small particles, includingresidual sand, in the liquid waste entering the small particleextraction unit 366 thus settle out of the liquid waste in this areaonto the top surface of the inclined or ramped floor 384. The vibrator394 is controllably operated to urge the settled small particles backtoward the small particle collection area 382A for subsequent extractionvia small particle outlet 396. The resulting liquid waste is removedfrom the liquid waste collection area 382B via the liquid waste outlet390 by the liquid waste extraction pump 392.

Referring now to FIG. 6, a schematic diagram of one illustrativeembodiment of a control system for controlling the liquid/solidseparation unit 30 is shown. In the illustrated embodiment, the shakermotor 376A is electrically connected to a conventional motor driver 400that is electrically connected to an actuator output of the PLC circuit102 via signal path 112 ₁₅. The shaker motor 376B is likewiseelectrically connected to a conventional motor driver 402 that iselectrically connected to another actuator output of the PLC circuit 102via signal path 112 ₁₆. The PLC circuit 102 is configured to control theoperation of the shaker motors 376A and 376B to shake the shaker table360 as described hereinabove to cause the liquid and small particleportion of the liquefied waste supplied by the sand separation unit 18to separate from the large waste particles carried by the liquefiedwaste.

The water supply line 26 is coupled to a water inlet of the shaker table360 via a water inlet valve 404 that is electrically connected toanother actuator output of the PLC circuit 102 via signal path 112 ₁₇.The PLC circuit 102 is operable to control the water inlet valve toselectively supply pressurized water; e.g., 40 psi, to the shaker table360 to rinse and clear the shaker table screen of trapped large wasteparticles. The large waste particle transport 370 is driven by aconventional motor 406 that is electrically connected to a conventionalmotor driver 408. The motor driver 408 is electrically connected toanother actuator output of the PLC circuit 102 via signal path 112 ₁₈.

The liquid waste outlet 390 of the small particle extraction unit 366 isfluidly coupled via a conduit 410 to an inlet of the liquid wasteextraction pump 392.

The liquid waste extraction pump 392 is driven by a conventional pumpdriver 412 that is electrically connected to another actuator output ofthe PLC circuit 102 via signal path 112 ₂₀. The outlet of the pump 392is fluidly connected to the liquid waste outlet, LWO, of theliquid/solid separation unit 30 by conduit 414, and a pair ofmechanically actuated butterfly valves, BV, are disposed in-line withconduits 412 and 414 on either side of the liquid waste extraction pump392 to allow for maintenance or replacement of pump 392 as needed. Thesmall particle outlet port 396 of the small particle extraction unit 366is fluidly coupled via a conduit 416 to the small particle outlet, SPO,of the liquid/solid separation unit 30. A small particle outlet valve418 is disposed in-line with conduit 416 and is electrically connectedto another actuator outlet of the PLC circuit 102 via signal path 112₂₁. The vibrator 394 is electrically connected to a further actuatoroutput of the PLC circuit 102 via signal path 112 ₁₉, and the PLCcircuit 102 is configured to control operation of the small particleextraction unit 366 as described hereinabove via control of the liquidwaste extraction pump 392, the small particle outlet valve 418 and thevibrator 394.

The liquid/solid separation unit 30 further includes a number of sensorsproviding sensory information to the PLC circuit 102 relating to variousoperational conditions of unit 30. For example, the small particleextraction unit 366 includes a level sensor 104 ₄ in fluid communicationtherewith, which in the illustrated embodiment is implemented as apressure sensor disposed in fluid communication with the interior of thesmall particle extraction unit along the incline or ramp 384.

Alternatively, the level sensor 104 ₄ could be implemented using one ormore other known level sensors. In any case, the level sensor 104 ₄ iselectrically connected to a sensor input of the PLC circuit 102 viasignal path 106 ₄, and the PLC circuit 102 is configured to determinethe liquid waste level within the small particle extraction unit 366 viathe sensor signal produced by the level sensor 104 ₄. Unit 30 furtherincludes a conventional flow meter or other known flow rate sensor 104 ₅disposed in-line with the liquid waste outlet conduit 414 andelectrically connected to another sensor input of the PLC circuit 102via signal path 106 ₉. The flow sensor 104 ₅ produces a sensor signalfrom which the PLC circuit 102 may determine the flow rate of liquidwaste flowing out of the liquid waste outlet, LWO, of the liquid/solidseparation unit 30. A pressure sensor 104 ₆ is also disposed in fluidcommunication with the liquid waste outlet conduit 414, and iselectrically connected to another sensor input of the PLC circuit 102via signal path 106 ₁₀. The pressure sensor 104 ₆ produces a sensorsignal from which the PLC circuit 102 may determine the pressure of theliquid waste flowing out of the liquid waste outlet, LWO, of the unit30.

Additionally, the small particle extraction unit 366 includes aconventional small particle float 398 positioned proximate or adjacentto the small particle collection area 382A of unit 366, and anassociated small particle float sensor 104 ₇ that is electricallyconnected to another sensor input of the PLC circuit 102 via signal path106 ₁₁. The position of the small particle float 398 varies with thequantity of small particles collected in the small particle collectionarea 382A, and in the illustrated embodiment the small particle floatsensor 104 ₇ is a switch that changes state when the small particlefloat 398 reaches a predefined height as the result of a sufficientquantity of small particles collected in the small particle collectionarea 382A of unit 366. The small particle float sensor 104 ₇ mayalternatively be implemented as an analog or other sensor producing asignal indicative of the position of the small particle float 398relative to a reference position. In any case, the small particle floatsensor 104 ₇ produces a signal from which the PLC circuit 102 maydetermine whether the quantity or level of small particles in the smallparticle collection area 382A of the small particle extraction unit 366has reached a quantity or level that merits removal of the collectedsmall particles.

Referring now to FIG. 7, a flowchart of one illustrative embodiment of asoftware control algorithm 420 for controlling the liquid/solidseparation unit 30 via the control system illustrated in FIG. 6 isshown. Control algorithm 420 is stored within, or programmed into, thePLC circuit 102, and the PLC circuit 102 is operable to executealgorithm 420 to control the operation of the liquid/solid separationunit 30. The control algorithm 420 includes a number of different andindependently executing control routines, and each of these differentcontrol routines will be described separately. For example, the controlalgorithm 420 includes a first control routine 422 for controlling theoperation of the shaker table 360. Control routine 424 begins at step424 where the PLC circuit 102 is operable to continuously operate theshaker motors 376A and 376B, as liquefied waste is supplied to theshaker table 360 via the liquefied waste inlet 362, by controlling themotor drivers 400 and 402 respectively. Thereafter at step 426, the PLCcircuit 102 is operable to periodically open the water supply valve 404for a time period, T1, to rinse and clear the shaker table screen, andthen to close the water inlet valve 404. The time period T1 is selectedto allow for the clearing of large waste particles trapped on the topscreen surface, and will depend upon the amount, size and density of thelarge waste particles carried by the liquefied waste, the porosity ofthe screen or mesh structure mounted within the shaker table 360 andother factors. In any case, execution of the control routine 422 loopsfrom step 426 back to step 424.

The liquid/solid separation unit control algorithm 420 further includesanother control routine 428 for controlling removal of liquid waste fromthe small particle extraction unit 366. Control routine 428 begins atstep 430 where the PLC circuit 102 is operable to determine the liquidlevel (LL) in the small particle extraction unit 366. In the illustratedembodiment, the PLC circuit 102 is operable to execute step 430 byprocessing the pressure signal produced by the pressure sensor 104 ₄ ina known manner to determine the liquid waste level within the smallparticle extraction unit 366. Thereafter at step 432, the PLC circuit102 is operable to compare LL to a first liquid level threshold,LL_(TH1), where LL_(TH1) corresponds to a predefined liquid level abovewhich it is desirable to remove liquid waste from the small particleextraction unit 366. Thus, if the PLC circuit 102 determines at step 432that LL is greater than LL_(TH), execution of the control routine 428advances to step 434 where the PLC circuit 102 is operable to activatethe liquid waste outlet pump 392. From step 434, execution of thecontrol routine 428 loops back to step 430.

If, at step 432, the PLC circuit 102 determines that LL is not greaterthan LL_(TH1), execution of the control routine 428 advances to step 436where the PLC circuit is operable to compare LL to a second liquid levelthreshold, LL_(TH2), where LL_(TH2) corresponds to a predefined liquidlevel at or below which it is desirable to cease removing liquid wastefrom the small particle extraction unit 366. Thus, if the PLC circuit102 determines at step 436 that LL is less than or equal to LL_(TH2),execution of the control routine 428 advances to step 438 where the PLCcircuit 102 is operable to deactivate the liquid waste outlet pump 392.From step 438 and from the “no” branch of step 436, execution of thecontrol routine 428 loops back to step 430.

The liquid/solid separation unit control algorithm 420 includes yetanother control routine 440 for controlling the removal of collectedsmall particles from the small particle extraction unit 366. Controlroutine 440 begins at step 442 where the PLC circuit 102 is configuredto periodically operate the vibrator 394 for a time period, T2, to urgesmall particles settled on the inclined or ramped floor 384 downwardlytoward the small particle collection area 382A of the small particleextraction unit 366. The time period T2 is selected to allow asubstantial amount of the small particles settled onto the top surfaceof the inclined or ramped floor 384 to move down the inclined or rampedfloor 384 and into the small particle collection area 382A, and willdepend upon the amount, size and density of the small particles presentin the liquid waste, the vibrating strength of the vibrator 394 andother factors.

In any case, execution of the control routine 440 advances from step 442to step 444 where the PLC circuit 102 is operable to monitor the output,SF, of the small particle float sensor 104 ₇. Thereafter at step 446,the PLC circuit 102 is operable to compare SF to a threshold sensorvalue, SF_(TH). If, at step 446, SF is greater than or equal to SF_(TH),execution of control routine 440 advances to step 448, and otherwiseloops back to step 442. In embodiments of the liquid/solid separationunit 30 wherein the small particle float sensor 104 ₇ is provided in theform of a switch, the threshold sensor value SF_(TH) corresponds to oneof two switch states; e.g., high or low, and the PLC circuit 102 isoperable to execute step 446 by determining whether SF is equal to theswitch state triggered by the small particle float 398 when the smallparticle collection area 382A has a predefined quantity of smallparticles collected therein. In embodiments wherein the small particlefloat sensor 104 ₇ is provided in the form of a conventional smallparticle float position sensor, the threshold sensor value SF_(TH)corresponds to a position of the small particle float 398, relative to areference position, when the small particle collection area 382A has thepredefined quantity of small particles collected therein. In any case,the PLC circuit 102 is operable at step 448 to open the small particleoutlet valve 418 for a time period T3, and then to close the smallparticle outlet valve 418. The time period T3 is selected to allow forremoval of a substantial portion of the small particles collected in thesmall particle collection area 382A, and will depend upon the triggerheight of the small particle float 398, the dimensions of the smallparticle collection area 382A and other factors. In any case, executionof the control routine 440 loops back to step 442. The sensoryinformation provided by the flow sensor or meter 104 ₅ and the pressuresensor 104 ₆ is used to control the speed of the liquid waste outletpump 392 in relation to the speed of another liquid waste outlet pump(474) in the pH adjustment stage 38 to provide for proper pump operationand a specified liquid waste flow rate as will be described in greaterdetail hereinafter with respect to FIGS. 8A, 8B and 9.

Referring now to FIG. 8A, a schematic diagram of one illustrativeembodiment of the pH adjustment unit 38 and corresponding control systemthat forms part of the waste stream pre-treatment system 12 is shown. Inthe illustrated embodiment, the pH adjustment unit 38 includes an acidsupply source 450 fluidly coupled to a liquid inlet of a liquid mixer454 via a conduit 452. The liquid waste conduit 40 defining the liquidwaste inlet, LWI, of the pH adjustment unit 38 is also fluidly coupledto conduit 452 between the acid supply source 450 and the liquid mixer454. In one embodiment, the liquid mixer 454 is implemented in the formof a length of conduit configured with a number of sharp turns tofacilitate mixing of the liquid waste as it flows therethrough.Alternatively, the liquid mixer 454 may be a tank or other conventionalliquid mixing structure that may include one or more conventionalagitators operable to mix the liquid waste. In any case, the liquidmixer 454 has a liquid outlet in fluid communication with a liquidoutlet conduit 456.

The acid supply source 450 includes an acid storage tank, and in theillustrated embodiment the acid storage tank is provided in the form ofa double-walled acid tank 458 having a pair of acid outlets each coupledvia a ball valve, BV, to a conduit 460. In one embodiment, the acid tank458 is filled with a sulfuric acid solution, although tank 458 mayalternatively be filled with other acidic solutions or dry mixturesincluding, but not limited to, solutions or dry mixtures of inorganic ormineral acids such as hydrochloric acid, hydrobromic acid, nitric acid,sulfuric acid, and acidic salts thereof, phosphoric acid, and acidicsalts thereof, perchloric acid, and the like; and organic acids such ascarbonic acid, formic acid, acetic acid, and the like; and combinationsthereof. In the illustrated embodiment, the acid tank 458 includes anultrasonic or other suitable level sensor 104 ₁₀ in fluid communicationtherewith and electrically connected to a sensor input of the PLCcircuit 102 via signal path 106 ₁₄. The PLC circuit 102 is operable tomonitor the acid solution level within the acid tank 458 by monitoringthe signal produced by the level sensor 104 ₁₀, and activate aconventional indicator when the acid solution level drops below athreshold acid level to prompt a technician to add acid solution to theacid tank 458.

The conduit 460 is fluidly coupled through a pair of ball valves, BV, toacid solution inlets of a pair of acid solution pumps 464 and 466. Afirst conventional pump driver 468 is electrically connected to the pump464, and is also electrically connected to an actuator output of the PLCcircuit 102 via signal path 112 ₂₂. A second conventional pump driver470 is electrically connected to the pump 466, and is also electricallyconnected to another actuator output of the PLC circuit 102 via signalpath 112 ₂₃. Acid solution outlets of the acid solution pumps 464 and466 are fluidly coupled through a series of butterfly and ball valves,BV, to conduit 452. The PLC circuit 102 is operable to control the acidsolution pumps 464 and 466 to controllably supply the acid solutionstored in the acid tank 458 to the inlet of the mixer 454 via conduit452. The various ball and butterfly valves, BV, are mechanicallyactuated valves, and are included to allow for maintenance and/orreplacement of the acid tank 458 and acid pumps 464 and 466, and/or toisolate the acid tank 458 from the remainder of the acid supply source450 or to isolate the acid supply source 450 from the liquid mixer 454.

As shown in phantom in FIG. 8A, the pH adjustment unit 38 mayalternatively or additionally include a base supply source 472 having abase solution outlet fluidly coupled to the inlet of the mixer 454 viaconduit 452. In embodiments including the base supply source 472, it maybe configured identical to the acid supply source 450 except that theacid tank 458 will be replaced with a base tank filled with a suitablebase in solution or as a dry mixture including, but not limited to,inorganic bases such as hydroxides such as sodium, potassium, cesium,ammonium, and like hydroxides; carbonates such as sodium, potassium,ammonium, and like carbonates; bicarbonates such as sodium, potassium,ammonium, and like bicarbonates, phosphates such as sodium, potassium,ammonium, and like phosphates; organic bases such as amines, substitutedamines such as alkyl, dialkyl, and trialkylamines, tetraalkylammoniumsalts, heteroaryls such as pyridines, pyridazines, pyrimidines, andpyrazines, and combinations thereof.

The outlet conduit 456 is fluidly coupled through a series of butterflyvalves, BV, to the inlet of a liquid waste outlet pump 474 having a pumpoutlet defining the liquid waste outlet, LWO, of the pH adjustment unit38 and fluidly coupled to conduit 42. A conventional pump driver 476 iselectrically connected to the pump 474, and is also electricallyconnected to another actuator output of the PLC circuit 102 via signalpath 112 ₂₄. The PLC circuit 102 is operable to control the liquid wasteoutlet pump 474 to controllably supply liquid waste to the wastefermentation system 14 via conduit 42.

The pH adjustment unit 38 may further include a number of conduits andassociated butterfly valves, BV, coupled to the liquid waste outletconduit 456 between the outlet of the liquid mixer 454 and the inlet ofthe liquid waste outlet pump 474 to allow for the cleaning/sterilizationof the outlet liquid waste outlet of the pH adjustment unit 38 and theliquid waste inlet of the waste fermentation system 14. Because suchconduits are used only for the purpose of cleaning and sterilizingportions of the pH adjustment unit 38 and waste fermentation system 14,and are generally not used during the normal, continuous flow operatingmode of the biomaterial waste processing system 10, the inlets andoutlets of such conduits to and from the pH adjustment unit 38 are notshown in FIG. 1 for ease of illustration, but are shown in FIG. 8A toillustrate the cleaning/sterilization flow paths relative to the pHadjustment unit 38. In the illustrated embodiment, for example, thewater inlet conduit 26 is fluidly coupled through a butterfly valve,BVA, to a conduit 480 coupled through another butterfly valve, BVC, tothe liquid waste outlet conduit 456. A cleaning agent conduit 478 iscoupled through another butterfly valve, BVB, to conduit 480, and a pairof butterfly valves, BVD and BVE, are disposed in-line with conduit 456;one, BVD, between the junction with conduit 480 and the outlet of theliquid mixer 454 and the other, BE, between the junction with conduit480 and the inlet of the pump 474. The conduit 78 fluidly connected tothe liquid outlet, LO, of the residual liquid processing unit 16 mayfurther be coupled to the junction of conduits 456 and 480 throughanother butterfly valve, BVF, and yet another conduit 484 may be coupledto conduit 78 downstream of the butterfly valve, BVF. The conduit 484may be coupled to the liquid waste return conduit 76 through yet anotherbutterfly valve, BVG. In a cleaning/sterilization mode, valves BVA, BVB,BVE and BVF may be opened while valve BVG is closed, and a cleaningagent may be added to conduit 478 such that a mixture of cleaning agentand water is circulated through a portion of conduit 456, through theliquid waste outlet pump 474, through the liquid waste outlet conduit 42and at least a portion of the waste fermentation system 14. When theseconduits and pump 474 have been sufficiently cleaned/sterilized, valvesBVB and BVF may be closed and valve BVG opened to flush the cleaningpath with clean water. Thereafter, valve BVA may be closed, and valvesBVD may be opened to resume normal, continuous flow operation of thebiomaterial waste processing system 10.

The pH adjustment unit 38 further includes a number of sensors providingsensory information to the PLC circuit 102 relating to variousoperational conditions of the pH adjustment unit 38. For example, unit366 includes an inlet conductivity sensor 104 ₈ in fluid communicationwith the liquid waste inlet conduit 40, and electrically connected to asensor input of the PLC circuit 102 via signal path 106 ₁₂. The inletconductivity sensor 104 ₈ produces an inlet conductivity signal, Ci,corresponding to the electrical conductivity of the liquid waste streamentering the liquid mixer 454, and the PLC circuit 102 is configured toprocess Ci in a known manner to determine the pH level of the liquidwaste stream entering the liquid mixer 454. The pH adjustment unit 38may further include an outlet conductivity sensor 104 ₉ in fluidcommunication with the liquid waste outlet conduit 456, and electricallyconnected to another sensor input of the PLC circuit 102 via signal path106 ₁₃. The outlet conductivity sensor 104 ₉ produces an outletconductivity signal, Co, corresponding to the electrical conductivity ofthe liquid waste exiting the liquid mixer 454, and the PLC circuit 102is configured to process Co in a known manner to determine the pH levelof the liquid waste stream exiting the liquid mixer 454. The PLC circuit102 is configured to adjust the pH level of the liquid waste streampassing through the liquid mixer 454 to a target pH level by controllingthe amount of acid solution entering conduit 452 (and/or the amount ofbase solution entering conduit 452) based on the inlet conductivitysignal, Ci, alone, or alternatively based on the inlet conductivitysignal, Ci, and the outlet conductivity signal, Co.

In embodiments of the biomaterial waste processing system 10 configuredto process liquefied animal waste, the pH level of the liquid wastestream entering the pH adjustment unit 38 will generally be at leastslightly basic, whereas optimal liquid waste processing conditions inthe subsequent waste fermentation system 14 are often generally acidic;for example, fermenting organisms such as yeasts exhibit higherfermentation rates at pH levels less than about 7, and illustrativelyless than about 5. It is appreciated that the fermenting organism ororganisms selected for inclusion in the fermentation system 14 will havea pH level that is optimum for fermentation. It is further appreciatedthat many organisms have a range of pH levels that might be used forfermentation. For those organisms, the pH may be adjusted to nearoptimum levels for fermentation in order to satisfy other criteria, suchas diminishing the proliferation or growth of a competing organism. Inthe illustrated embodiment, the pH adjustment unit 38 is accordinglycontrolled by the PLC circuit 102 to selectively add acid solution tothe liquid waste stream entering the liquid mixer 454 to adjust the pHlevel of the liquid waste exiting the liquid mixer 454 to a targetacidic pH level. In embodiments of the biomaterial waste processingsystem 10 configured to process animal waste, the target pH level maybe, for example, 4.0. In other embodiments, the biomaterial waste streammay be too acidic for optimal processing by the waste fermentationsystem 14, and in such embodiments the pH adjustment unit 38 may includethe base supply source 472, and the PLC circuit 102 may be controlled insuch embodiments to selectively add base solution to the liquid wasteentering the liquid mixer 454 to adjust the pH level of the liquid wasteexiting the liquid mixer 454 to the target pH level. In still otherembodiments, regardless of the pH level of the incoming liquid wastestream, the pH adjustment unit 38 may include both of the acid and basesupply sources 450 and 472 to provide for pH adjustment of the incomingliquid waste stream in either pH direction.

Referring now to FIG. 8B, a schematic diagram of another illustrativeembodiment of the pH adjustment unit 38′ and corresponding controlsystem that forms part of the waste stream pre-treatment system 12 isshown. The pH adjustment unit 38′ and associated control systemillustrated in FIG. 8B is identical in many respects to the pHadjustment unit 38 and associated control system illustrated in FIG. 8A,and like numbers are therefore used to identify like components. In theembodiment illustrated in FIG. 8B, a biomaterial waste settling tank 457is interposed between the mixer 454 and the pump 474. More particularly,the biomaterial waste outlet of the mixer 454 is fluidly coupled to abiomaterial waste inlet of the settling tank 457 via a conduit 456, anda biomaterial waste outlet of the settling tank 457 is fluidly coupledto the junction of the conduits 480 and 482. An air or gas outlet of thesettling tank 457 is fluidly coupled to the gas outlet 68 of the wastefermentation system 14. A solid waste outlet of the settling tank 457 isfluidly coupled to an inlet of a solid waste outlet pump 465 having apump outlet fluidly coupled to the precipitated waste outlet conduit 80.A conventional pump driver 467 is electrically connected to the pump465, and is electrically connected to another actuator output of the PLCcircuit 102 via signal path 112 ₂₅. The PLC circuit 102 is operable tocontrol the solid waste outlet pump 465 to controllably pump solid wastefrom the settling tank 457 via the conduit 80.

In another embodiment, a settling system is described (see, for example,the illustrative settling system 457 shown in FIGS. 8B-8E, and a systemcontaining the same shown in FIG. 8A). The settling system is generallydesigned to remove particulates, including fine particulates from abiomaterial waste stream. In one aspect, the particulates or fineparticulates include sand, straw, fibers, and the like. It isappreciated that the settling system may be advantageously used toremove small amounts of particulates from a biomaterial waste streamthat has already been treated by another separation process, includingthe separation processes described herein, such as an illustrativeliquid solid separation unit 30 (see FIG. 6), and the like. In anotheraspect, the settling system is used as a separation process prior to anadditional separation process, including the separation processesdescribed herein, such as illustrative aggregation unit 2110 designed toremove dissolved solids form aqueous solutions (see FIG. 49), and thelike. In another aspect, the settling system is an independent orstand-alone separation system.

FIG. 8B shows an illustrative configuration of this alternate solidseparation unit 457 following a pH adjustment unit. FIGS. 8C and 8D showside and top views, respectively, of an illustrative cylindricalembodiment of settling tank 457 defined by an outer wall 471, a slopingtop 473, such as a domed top, and a sloping bottom 475, such as a domedbottom. It is appreciated that domed or sloping top 473, and domed orsloping bottom 475 may each facilitate the removal of material fromsettling tank 457. Settling tank 457 is fitted with a biomaterial wastestream inlet WI entering outer wall 471, a clarified liquid outlet CLOexiting outer wall 471, an air outlet AO exiting sloping top 473, and asolids outlet SO exiting sloping bottom 475. Solids outlet SO is acircular opening in sloped bottom 475, and is illustratively largecompared to inlet WI, air outlet AO, and clarified liquid outlet CLO.Solids outlet SO may operate solely by gravity feed, or may beoptionally fitted with a pump and/or auger attached at conduit 495 tofacilitate removal of precipitated solids from settling tank 475.Removed solids may be transported to other optional processes by aconveyer system, enclosed pipe, and the like, depending upon the nature,viscosity, water content, and other properties of the removed solids, asappropriate. Settling tank 457 is supported above ground by supports(not shown), each being long enough to accommodate solids outlet SO andany other optional system for transporting solids removed from settlingtank 457.

The interior of settling tank 457 is fitted with liquid sparger 477,cone 479, and four vertical plates 481. The top edge of liquid sparger477 includes clarified liquid inlets CLI in fluid communication with theliquid contents of settling tank 457, and also in fluid communicationwith conduit 483 connected to clarified liquid outlet CLO. Cone 479 isradially centered on the vertical axis of settling tank 457, and isvertically positioned in tank 457, illustratively about midway in thecylindrical portion of settling tank 457, or slightly lower. The heightof cone 479 is in the range from about 55% to about 75%, andillustratively about 60%, of the height of the cylindrical portion ofsettling tank 457. In one aspect, bottom edge 485 of cone 479 spans mostof the horizontal dimension of the interior space of settling tank 457.In another aspect, bottom edge 485 of cone 479 spans the majority of thediameter of settling tank 457, such as in the range from about 75% toabout 90%, or from about 80% to about 85% of the diameter of settlingtank 457. Apex 487 of cone 479 is in fluid communication with air outletAO via conduit 489, allowing trapped air to escape. Waste stream inletWI extends into the interior of cone 479 to biomaterial waste streamoutlet WO. Waste stream inlet WI is positioned near apex 487, butsufficiently below the opening to conduit 489 to allow trapped air toescape without simultaneously aspirating significant amounts of liquidphase.

Vertical plates 481, in the shape of right triangles are attached to theouter surface of cone 479 at 90 degree intervals when viewed from thetop (see FIG. 8D). Vertical plates 481 extend to or nearly to the bottomedge 485 of cone 479, and to or nearly to the apex 487 of cone 479. Inone illustrative variation, vertical plates 481 extend to bottom edge485 and nearly to the apex 487 of cone 479.

In another illustrative variation, the cylindrical portion of settlingtank 457 has a medium-sized or nearly equal aspect ratio, such as anaspect ratio in the range from about 1.1 to about 1.5.

In one illustrative embodiment, the cylindrical portion of settling tank457 is about 12 feet (3.7 m) in height and 11 feet (3.4 m) in diameter,cone 479 is about 7.5 feet (2.3 m) in height and about 9.5 feet (2.9 m)in diameter, and cone 479 is positioned about 2 feet (0.6 m) from thebottom of the cylindrical portion of, and about 1 foot (0.3 m) frominner wall 491 of settling tank 157. Solids outlet SO is about 30 inches(0.8 m) in diameter.

FIG. 8E shows the flow of liquid and solid components of the biomaterialwaste stream entering settling tank 457 via waste stream inlet WI.

Referring to FIG. 8E, liquid biomaterial waste (hashed arrow) entersinlet WI and proceeds to the interior of cone 479. The configuration ofcone 479 will naturally create a vortex in the liquid moving down cone479, under gravity flow and optionally some residual pressure, creatingthereby a Coriolis, centrifugal, or centripetal force directly radiallyoutward to the sides of cone 479 (hashed arcing arrow). Net velocitywithin cone 479 is vertically downward (hashed arrow), allowingsubstantial settling of particulates and other solid components of thebiomaterial waste stream. Contributing to the generated radially outwardvelocity is the movement of liquid away from the outer and bottom edgeof cone 479. Because the amount of mass removed via clarified liquidoutlet CLO is greater, illustratively as high as ten-fold greater, thanthe amount of mass removed via solids outlet SO, net velocity outsidecone 479 and above bottom edge 485 is vertically upward (open arrows).Conversely, net velocity outside cone 479 and below bottom edge 485 isvertically downward (solid arrows). Circular rotation of liquid outsidecone 479 and above bottom edge 485 may be opposite that of circularrotation of liquid inside cone 479 and/or outside cone 479 and belowbottom edge 485. Vertical plates 481 are positioned to decrease or limitthe circular rotation of liquid outside cone 479 and above bottom edge485 to reduce, minimize, or preclude the generation of turbulence at theinterface between mass moving vertically upward and mass movingvertically downward. It is appreciated that the circular rotation ofliquid outside cone 479 and below bottom edge 485 may create a sweepingeffect to facilitate movement of settling solid components to solidsoutlet SO, and also facilitated by sloping bottom 475. It is furtherappreciated that other particulates or solids that are less dense thanthe bulk liquid biomaterial waste stream entering cone 479 via conduit493 will float on top of the entering biomaterial waste stream at apex487, be trapped thereby, and be effectively separated from the enteringbiomaterial waste stream to produce clarified liquid.

Liquid sparger 477 is positioned sufficiently high in settling tank 457to maximize the laminar flow of clarified liquid into clarified liquidinlets CLI positioned on the top face of sparger 477, thus maximizingthe clarity of liquid exiting settling tank 457 via conduit 483 andclarified liquid outlet CLO.

Referring now to FIG. 9, a flowchart of one illustrative embodiment of asoftware control algorithm 490 for controlling the pH adjustment unit 38is shown. Control algorithm 490 is stored within, or programmed into,the PLC circuit 102, and the PLC circuit 102 is operable to executealgorithm 490 to control the operation of the pH adjustment unit 38. Thecontrol algorithm 490 includes a number of different and independentlyexecuting control routines, and each of these different control routineswill be described separately. For example, the control algorithm 490includes a first control routine 492 for controlling the flow of liquidwaste out of the liquid waste outlet, LWO, of the pH adjustment unit 38.Control routine 492 begins at step 494 where the PLC circuit 102 isoperable to determine the pressure, P, of the liquid waste streambetween the liquid/solid separation unit 30 and the pH adjustment unit38; i.e., the pressure signal produced by the pressure sensor 104 ₆ ofthe liquid/solid separation unit 30 of FIG. 6. Thereafter at step 496,the PLC circuit 102 is operable to determine the flow rate, FR, of theliquid waste stream exiting the liquid/solid separation unit 30; i.e.,the flow rate signal produced by the flow rate sensor or meter 104 ₅.Thereafter at step 498, the PLC circuit 102 is operable to control theoperation of the liquid waste outlet pump of the liquid/solid separationunit 30 of FIG. 6; i.e., pump 392, and the operation of the liquid wasteoutlet pump of the pH adjustment unit 38 of FIG. 8A or 8B; i.e., pump474 to maintain positive pressure within conduits 414 and 40, and tomaintain a flow rate of the liquid waste stream through the pHadjustment system 38 and into liquid waste conduit 42 near a target flowrate, FRT; e.g., 100 gpm. The PLC circuit 102 is operable to executestep 498 by controlling the relative speeds of pumps 392 and 474 toprevent pump cavitation by maintaining a positive pressure therebetween,while also controlling the speeds of both pumps 392 and 474 to maintainFR near FRT. From step 498, execution of the control routine 492 loopsback to step 494.

The pH adjustment unit control algorithm 490 includes another controlroutine 500 for continuously adjusting the pH level of the liquid wastestream flowing through the pH adjustment unit 38. In the illustratedembodiment, the control routine 500 begins at step 502 where the PLCcircuit 102 is operable to determine the inlet conductivity, Ci,corresponding to the conductivity of the liquid waste stream enteringthe liquid mixer 454. The PLC circuit 102 is operable to execute step502 by monitoring the signal produced by the conductivity sensor 104 ₈.Thereafter at step 504, the PLC circuit 102 is operable to determine theoutlet conductivity, Co, corresponding to the conductivity of the liquidwaste stream exiting the liquid mixer 454. The PLC circuit 102 isoperable to execute step 504 by monitoring the signal produced by theconductivity sensor 104 ₉. Following step 504, the PLC circuit 102 isoperable at step 506 to control the acid pumps 464 and 466 based on Cialone, or on Ci and Co, to drive Co to a target conductivity value,C_(T). In one embodiment, the PLC circuit 102 may be configured todetermine the flow rate of acid solution required to change Co to C_(T)as a function of the inlet conductivity, Ci, of the liquid waste streamentering the liquid mixer 454 and the flow rate, FR, of the liquid wastestream entering the liquid mixer 454, and to control the acid pumps 464and 466 to supply the acid solution to the liquid mixer 454 at therequired acid solution flow rate. Alternatively, the PLC circuit 102 maybe configured to determine the flow rate of acid solution required tochange Co to C_(T) as a function of the conductivity differential; e.g.,Co−Ci, across the liquid mixer 454. In either case, execution of thecontrol routine 500 loops back to step 502 in embodiments of the pHadjustment unit 38 that do not include a base supply source 472. Inembodiments of the pH adjustment unit 38 including the base supplysource 472, however, the control routine 500 may additionally oralternatively to step 506 include step 508, as shown in phantom in FIG.9, wherein the PLC circuit 102 is operable similarly as just describedwith respect to step 506 to control base solution pumps contained withinthe base supply source 472 based on Ci, or on Ci and Co, to drive Co toC_(T). Execution of the control routine 500 loops from step 508 back tostep 502.

Referring now to FIG. 10, a schematic diagram of one illustrativeembodiment of the air system 56 and corresponding control system thatforms part of the biomaterial waste stream processing system 10 isshown. In the illustrated embodiment, the air system 56 includes aconventional air compressor 520 fluidly coupled to a conventional airdryer 524 via a conduit 522. A pressure sensor 122 ₁ is disposed influid communication with the air compressor 520, and is electricallyconnected to a sensor input of the PLC circuit 120. The air dryer 524 isoperable in a known manner to dry the pressurized air supplied by theair compressor 520, and to supply the dried air to an air conduit 526having a pair of ball valves, BV, disposed in-line therewith. Anotherair conduit 530 extends from air conduit 426 and through another ballvalve to an air inlet of a conventional pressure regulator 532. An airoutlet of the pressure regulator 532 is fluidly coupled via another airconduit 534, through another ball valve, BV, to air outlet conduits 58,60 and 62.

Another conduit 530 is fluidly coupled to the junction of air conduits526 and 528, and is also coupled to the steam inlet conduit 64 throughanother ball valve, BV. Conduit 530 is also coupled to conduit 534through a pair of ball valves, BV, and another conduit 538 is coupled toconduit 536 between the pair of ball valves, BV. The conduit 528 is alsocoupled to steam outlet conduit 66 through another pair of ball valves,BV. Another conduit 540 couples a drain outlet of the pressure regulator532 to the drain conduit 67 through another ball valve, BV.

In the illustrated embodiment, the pressure regulator 532 may bemanually set to regulate the pressurized air supplied by the aircompressor 520 and air dryer 524 to a desired air pressure, wherein theair regulated to the desired air pressure is supplied by the pressureregulator to air outlets 58, 60 and 62. The various ball valves, BV, maybe selectively opened to allow a combination of steam and pressurizedair to flow out of the steam conduit 66.

Referring now to FIG. 11, a schematic diagram of one illustrativeembodiment of the water system 24 and corresponding control system thatforms part of the biomaterial waste stream processing system 10 isshown. In the illustrated embodiment, tap water; e.g., 40 psi, issupplied via water conduit 25 to a tap water inlet, TWI, of the watersystem 24 that is coupled through a ball valve, BV, to an inlet of aconventional water softener 550. An outlet of the water softener 550 iscoupled through a pair of ball valves, BV, and a control valve 554disposed therebetween to a soft water surge tank 556 having a pressuresensor 122 ₂ or other suitable fluid level sensor in fluid communicationtherewith and electrically connected to a sensor input of the PLCcircuit 120 via signal path 124 ₂. The control valve 554 is electricallyconnected to an actuator output of the PLC circuit 120 via signal path130 ₁. The PLC circuit 120 is operable to maintain a sufficient amountof water within the soft water surge tank 556 by monitoring the signalproduced by the pressure sensor 122 ₂, processing this signal todetermine a level of water within the soft water surge tank 556, andcontrolling the control valve 554 to supply soft water from the watersoftener 550 to the soft water surge tank 556 when the water levelwithin the soft water surge tank 556 is below a threshold water level. Awater outlet of the soft water surge tank 556 is coupled through anotherball valve, BV, to the water outlet conduit 26.

In embodiments including the water system 24 illustrated in FIG. 11, thesoft water surge tank 556 also includes an overflow inlet coupledthrough another ball valve, BV, to an overflow conduit 558 extendingfrom the waste fermentation system 14. In an alternative embodiment, thewater system 24 may be omitted, and the tap water supplied via conduit25 may be instead used as the water source. In such embodiments, theoverflow conduit 558 may be routed to a suitable overflow container ormay instead be configured to spill overflow water to the ground.

Referring now to FIG. 12 a block diagram of one illustrative embodimentof the waste fermentation system 14 forming part of the biomaterialwaste processing system 10 is shown. In the illustrated embodiment, thewaste fermentation system 14 includes a sterilization unit 570 having aliquid waste inlet, LWI, fluidly coupled to the liquid waste inlet, LWI,of the waste fermentation system 14 and receiving the liquid biomaterialwaste stream via conduit 42, a sterilized liquid waste outlet, SLWO,supplying a stream of sterilized liquid biomaterial waste to asterilized liquid waste inlet, SLWI, of a fermentation unit 580 viaconduit 582 and a liquid waste return outlet, LWR, fluidly coupled tothe liquid waste return outlet, LWR, of the waste fermentation system14. The sterilization unit 570 further includes a sterilization steaminlet, SSTI, fluidly coupled to a sterilization steam outlet, SSTO, of asteam unit 572 via conduit 576, a sterilization steam outlet, SSTO,fluidly coupled to a sterilization steam inlet, SSTI, of the steam unit572 via conduit 576 and a cleaning steam inlet, CSI, fluidly coupled toa cleaning steam outlet, CSO, of the steam unit 572 via conduit 578. Thesterilization unit 570 further includes a number, L, of sensors eachproducing a sensor signal indicative of a corresponding operatingcondition of the sterilization unit 570, wherein L may be any positiveinteger. The “L” sensor signals are supplied to the PLC circuit 120 viaa corresponding number of signal paths as illustrated in FIG. 1. Thesterilization unit 570 further includes a number, K, of actuators eachresponsive to a corresponding actuator control signal supplied by thePLC circuit 120 to control a corresponding operating parameter of thesterilization unit 570. The sterilization unit 570 is generallyoperable, as will be described in greater detail hereinafter withrespect to FIGS. 13A-14C, to sterilize the liquid biomaterial wastestream supplied thereto via conduit 42 and provide a sterilized liquidbiomaterial waste stream to the fermentation unit 580 via conduit 582.

The temperature of the sterilization process performed by thesterilization unit 570 is controlled by the steam unit 572 configured tocontrollably circulate steam through the sterilization unit 570 viaconduits 574 and 576. The steam unit 572 further includes a water inlet,WI, fluidly coupled to the water inlet, WI, of the waste fermentationsystem 14 via conduit 26, and a chemical inlet, CHI, fluidly coupled tothe chemical inlet, CHI, of the waste fermentation system via conduit54. A pasteurization steam outlet, PSTO, of the steam unit 572 isfluidly coupled to a pasteurization steam inlet, PSTI, of apasteurization unit 594 via conduit 604, and a pasteurization steaminlet, PSTI, of the steam unit 572 is fluidly coupled to apasteurization steam outlet, PSTO, of the pasteurization unit 594 viaconduit 602. The steam unit 572 further includes a sample clean steamoutlet, SCSO, fluidly coupled to a sample clean steam inlet, SCSI, ofthe pasteurization unit 594 via conduit 606. A drain outlet, D, of thesteam unit 570 is fluidly connected to the liquid waste return outlet,LWR, of the waste fermentation system 14 via conduit 584, and anothersteam outlet, STO, of the steam unit 570 is fluidly connected to thesteam outlet, ST, of the waster fermentation system 14 via conduit 64.The steam unit 572 further includes a number, M, of sensors eachproducing a sensor signal indicative of a corresponding operatingcondition of the steam unit 572, wherein M may be any positive integer.The “M” sensor signals are supplied to the PLC circuit 120 via acorresponding number of signal paths as illustrated in FIG. 1. The steamunit 572 further includes a number, N, of actuators each responsive to acorresponding actuator control signal supplied by the PLC circuit 120 tocontrol a corresponding operating parameter of the steam unit 572. Thesteam unit 572 is generally operable, as will be described in greaterdetail hereinafter with respect to FIGS. 15-16 to provide for thecirculation of steam through the sterilization unit 570 and the steamunit 572 via conduits 574, 476 and 578, and also to provide for thecirculation of steam through the pasteurization unit 594 and the steamunit 572 via conduits 602 and 604.

In addition to the sterilized liquid waste inlet, SLWI, the fermentationunit 580 further includes a first inner air sparger air inlet, F1I, afirst outer air sparger inlet, F1O, a second inner air sparger airinlet, F2I, and a seed steam inlet, F12S, fluidly coupled to the airsystem 56 via conduits 58, 60, 62 and 66 respectively. First and secondseed inlets, SD1 and SD2, of the fermentation unit 580 are fluidlycoupled to conduits 46 and 50 respectively. A residual liquid outlet,RLO of the fermentation unit 580 is fluidly coupled to conduit 74, and agas outlet, GO, of the fermentation unit 580 is fluidly coupled toconduit 68. The fermentation unit 580 further includes a product outlet,POF, fluidly coupled to a product inlet, PIP, of the pasteurization unit594 via conduit 598, a waste return inlet fluidly coupled to a wastereturn outlet, WRO, of the pasteurization unit 594 and a water inlet,WI, fluidly coupled to the fresh water conduit 26.

The fermentation unit 580 further includes a coolant flow outlet, CFO,fluidly coupled to a coolant flow inlet, CFI, of a cooling tower unit586 via conduit 588, and a coolant flow inlet, CFI, fluidly coupled to acoolant flow outlet, CFO, of the cooling tower unit 586 via conduit 590.The temperature of the sterilized liquid biomaterial waste streamsupplied to the fermentation unit 580 via conduit 582 is controlled to atarget temperature by the cooling tower unit 586 configured tocontrollably circulate coolant fluid; e.g., water, through thefermentation unit 580 via conduits 588 and 590. The fermentation unit580 further includes a number, P, of sensors each producing a sensorsignal indicative of a corresponding operating condition of thefermentation unit 580, wherein P may be any positive integer. The “P”sensor signals are supplied to the PLC circuit 120 via a suitable numberof signal paths as illustrated in FIG. 1. The fermentation unit 580further includes a number, O, of actuators each responsive to acorresponding actuator control signal supplied by the PLC circuit 120 tocontrol a corresponding operating parameter of the fermentation unit580. The fermentation unit 580 is operable, as will be described ingreater detail hereinafter with respect to FIGS. 19-26B, to process theincoming sterilized biomaterial waste stream in a manner that producesfermenting organism and residual liquid. The residual liquid streamexits the fermentation unit 580 via the residual liquid outlet, RLO, andthe fermenting organism product is supplied to the pasteurization unit594 via the product outlet port, POF.

The cooling tower unit 586 further includes a chemical inlet, CHI,fluidly coupled to conduit 54, and an overflow outlet, OF, fluidlycoupled to conduit 558. As described hereinabove, in embodiments of thebiomaterial waste processing system 10 including a water system 24 ofthe type illustrated in FIG. 11, the overflow conduit 558 is fluidlycoupled to the soft water surge tank 556 for recovery of any overflowwater produced by the cooling tower unit 596. In embodiments of thebiomaterial waste processing system 10 that do not include a watersystem 24 of the type illustrated in FIG. 11, and alternatively receivetap water directly from a conventional water source, the overflowconduit 558 may be fluidly coupled to a suitable collection container orsystem, fluidly coupled to the liquid waste return conduit 76 or allowedto drain to the ground. In any case, the cooling tower unit 586 furtherincludes a drain outlet, D, fluidly coupled to the liquid waste returnoutlet, LWR, of the waste fermentation system 14 via conduit 592. Thecooling tower unit 586 further includes a number, J, of sensors eachproducing a sensor signal indicative of a corresponding operatingcondition of the cooling tower unit 586, wherein J may be any positiveinteger. The “J” sensor signals are supplied to the PLC circuit 120 viaa suitable number of signal paths as illustrated in FIG. 1. The coolingtower unit 586 further includes a number, I, of actuators eachresponsive to a corresponding actuator control signal supplied by thePLC circuit 120 to control a corresponding operating parameter of thefermentation unit 580. The cooling tower unit 586 is operable, as willbe described in greater detail hereinafter with respect to FIGS. 17-18B,to controllably circulate coolant fluid; e.g., water, to a portion ofthe fermentation unit 580 via conduits 588 and 590 to control thetemperature of the incoming sterilized liquid biomaterial waste streamto a target temperature.

The pasteurization unit 594 further includes a water inlet, WI, fluidlyconnected to the water inlet conduit 26, and a sample outlet, SMPL,fluidly coupled to a sample outlet conduit 600. The pasteurization unit594 further includes a number, R, of sensors each producing a sensorsignal indicative of a corresponding operating condition of thepasteurization unit 594, wherein R may be any positive integer. The “R”sensor signals are supplied to the PLC circuit 120 via a suitable numberof signal paths as illustrated in FIG. 1. The pasteurization unit 594further includes a number, I, of actuators each responsive to acorresponding actuator control signal supplied by the PLC circuit 120 tocontrol a corresponding operating parameter of the pasteurization unit594. The pasteurization unit 594 is operable, as will be described ingreater detail hereinafter with respect to FIGS. 27-28, to pasteurizeand store for later use the fermenting organism produced by thefermentation unit 580.

Referring now to FIG. 13A, a schematic diagram of one illustrativeembodiment of the sterilization unit 570 forming part of the wastefermentation stage 14 of FIG. 12 is shown. In the illustratedembodiment, the liquid waste inlet, LWI, is fluidly coupled to the wastestream inlet conduit 42 and to one end of another conduit 610 having anopposite end fluidly coupled through a butterfly valve, BVJ, a checkvalve, CV and another butterfly valve, BV, to an inlet of a liquid wastepump 612 having a pump outlet fluidly coupled through another butterflyvalve, BV, to one end of yet another conduit 614. The liquid waste pump612 is electrically connected to a conventional pump driver circuit 616that is also electrically connected to an actuator output of the PLCcircuit 120 via one of the “K” signal paths 130 ₂. The PLC circuit 120is configured to control the liquid waste pump 612 via the pump driver616 to control the flow of the liquid biomaterial waste stream throughthe sterilization unit 570.

One of the “L” sensors included within the sterilization unit 570 is aconventional flow rate sensor or flow meter 122 ₃ disposed in-line withconduit 610 between the butterfly valve BVJ and the check valve, CV, andelectrically connected to the PLC circuit 120 via signal path 124 ₃. Theflow rate sensor 122 ₃ is operable to produce a signal on signal path124 ₃ indicative of a flow rate of the liquid biomaterial waste streamflowing into the liquid waste inlet, LWI, of the sterilization unit 570.Another one of the “L” sensors included within the sterilization unit570 is a conventional pressure sensor 122 ₄ disposed in fluidcommunication with conduit 610 between the check valve, CV, and thebutterfly valve, BV, and electrically connected to the PLC circuit 120via signal path 124 ₄. The pressure sensor 122 ₄ is operable to producea signal on signal path 124 ₄ indicative of the pressure of the liquidbiomaterial waste stream entering the inlet of the liquid waste pump612.

Downstream of the outlet of the liquid waste pump 612, conduit 614passes through another ball valve, BV, a first fluid passageway of apost-sterilization heat exchanger HX1 of known construction, anotherball valve, BV, a butterfly valve, BV, and then through a first fluidpassageway of a pre-sterilization heat exchanger HX2 also of knownconstruction. After passing through another butterfly valve, BV, conduit616 is fluidly connected to an inlet of a sterilization loop 630.Between the butterfly valve, BV, adjacent the outlet of the liquid wastepump 612 and the ball valve leading to the heat exchanger HX1, anotherconduit 618 fluidly connects conduit 614 to one inlet of a pressurerelief valve 619 having an outlet coupled through a check valve, CV, tothe liquid outlet conduit 78 via conduit 620. A control valve 622 isfluidly connected at one end to the conduit 614 between the intersectionof conduit 614 with conduit 618 and the butterfly valve, BV, adjacent tothe outlet of the liquid waste pump 612, and at an opposite end to theconduit 620 between the pressure relief valve 619 and the check valve,CV. The control valve 622 is electrically connected to another actuatoroutput of the PLC circuit 120 via another one of the “K” signal paths130 ₃, and the PLC circuit 120 is operable to control liquid flowbetween conduits 614 and 618 via control of the control valve 622.Between the control valve 622 and the butterfly valve, BV, adjacent tothe outlet of the liquid waste pump 612, a pressure sensor 122 ₅ isdisposed in fluid communication with conduit 614 and electricallyconnected to a sensor input of the PLC circuit 120 via another one ofthe “L” signal paths 124 ₅.

Another conduit 624 is fluidly connected at one end to conduit 614between the butterfly valve, BV, adjacent to the outlet of the liquidwaste pump 612 and the pressure sensor 122 ₅, and is coupled throughanother butterfly valve, BVL, to the liquid outlet conduit 78. Yetanother conduit 626 is fluidly connected at one end to conduit 624between the intersection of conduit 614 and 624 and the butterfly valve,BVL, and is coupled through another butterfly valve, BVK, to thecleaning steam inlet, CSI, of the sterilization unit 570 which isfluidly coupled to conduit 578. Still another conduit 628 is fluidlyconnected at one end to the inlet conduit 612 between the liquid wasteinlet, LWI, of the sterilization system 570 and the butterfly valve,BVJ, and is coupled through another butterfly valve, BVI, to the liquidwaste return conduit 76. The junction of conduits 618 and 76 is coupledthrough yet another butterfly valve, BVH, to the junction of the liquidoutlet conduit 78 and conduit 624.

The sterilization steam inlet, SSTI, of the sterilization unit 570 thatis fluidly coupled to conduit 574 is also coupled through a controlvalve 634 and a butterfly valve, BV, to one end of a second fluidpassageway defined through the pre-sterilization heat exchanger HX2. Anopposite end of the second fluid passageway of HX2 is fluidly coupled toa conduit 632 that is coupled through another butterfly valve, BV, tothe sterilization steam outlet, SSTO, of the sterilization unit 570 andalso to conduit 576. The control valve 634 is electrically connected toanother actuator output of the PLC circuit 120 via another one of the“K” signal paths 130 ₄. The PLC circuit 120 is configured tocontrollably circulate steam or other temperature-controlled liquid fromthe steam unit 572 through the pre-sterilization heat exchanger HX2, viacontrol of the control valve 634, to controllably transfer heattherefrom via the pre-sterilization heat exchanger HX2 to the liquidbiomaterial waste stream flowing through conduit 614 to elevate thetemperature of the biomaterial waste stream to a sterilizationtemperature.

The sterilization loop 630 is illustratively provided as a conduitformed in a serpentine, looped or other suitable configuration, whereinthe length of the loop 630 and the cross-sectional flow area through theloop 630 define its volumetric capacity, and this volumetric capacity,in turn, defines the sterilization time of the loop 630. In general, thesterilization time of the liquid waste, and the liquid waste temperaturerequired to for such sterilization, is a function of the pH level of theliquid waste passing through the sterilization system 570. By loweringthe pH level of the liquid waste stream to an acidic level; e.g., pH4.0, the combination of time and temperature required for sterilizationof the liquid waste stream is also lowered below what would otherwise berequired at more neutral pH levels; e.g., pH 7.0. It is appreciated thatthe optimum pH level for sterilization of the liquid waste is dependentupon the competing organisms that are present in the liquid waste.Therefore, in variations of the sterilization process described herein,a pH level other than e.g. 4.0 is used to shorten the time required tosterilize the liquid waste.

Another one of the “L” sensors included within the sterilization unit570 is a conventional temperature sensor 122 ₆ disposed in fluidcommunication with conduit 614 between the ball valve, BV, disposedin-line with the conduit 614 downstream of the liquid waste outlet ofthe pre-sterilization heat exchanger HX2 and the inlet of thesterilization loop 630, and electrically connected to a sensor input ofthe PLC circuit 120 via another one of the “L” signal paths 124 ₆. Thetemperature sensor 122 ₆ may be alternatively positioned relative to thewaste stream outlet of the heat exchanger HX2 and the inlet of thesterilization loop 630, and is in any case operable to produce a signalon signal path 124 ₆ indicative of the temperature of the liquidbiomaterial waste stream exiting the waste stream outlet of thepre-sterilization heat exchanger 630 and entering the sterilization loop630. Yet another of the “L” sensors included within the sterilizationunit 570 is a sterilization loop outlet temperature sensor 122 ₇ ofknown construction and disposed in fluid communication with a conduit636 fluidly coupled to the outlet of the sterilization loop 630, andelectrically connected to another sensor input of the PLC circuit 120via another one of the “L” signal paths 124 ₇. The temperature sensor122 ₄ is operable to produce a signal on signal path 127 ₄ indicative ofthe temperature of the liquid biomaterial waste stream exiting theoutlet of the sterilization loop 630.

The fluid outlet of the sterilization loop 630 is fluidly coupledthrough another ball valve, BV, though a second fluid passageway of thepost-sterilization heat exchanger HX1, and then through another ballvalve, BV, to an inlet of a diverter valve 638. Heat from the sterilizedbiomaterial waste stream exiting the sterilization loop 630 and flowingthrough conduit 636 is transferred via the post-sterilization heatexchanger HX1 to the biomaterial waste stream flowing through conduit614 in order to pre-heat the biomaterial waste stream prior to enteringthe pre-sterilization heat exchanger HX2. Inclusion of thepost-sterilization heat exchanger HX1 thus allows for recovery of someof the heat transferred by the pre-sterilization heat exchanger HX2 tothe biomaterial waste stream, and thereby reduces the temperaturerequirements of the steam or other temperature-controlled liquidsupplied to the pre-sterilization heat exchanger HX2 via control valve634 below what would otherwise be required in the absence of thepost-sterilization heat exchanger HX1.

One outlet of the diverter valve 638 is fluidly coupled to the liquidwaste inlet conduit 610 between the check valve, CV, and the butterflyvalve, BV, adjacent to the inlet of the liquid waste pump 612. Anotheroutlet of the diverter valve 638 is fluidly coupled via conduit 642 toan inlet of a pressure control valve 644, and the outlet of the pressurecontrol valve 644 defines the sterilized liquid waste outlet, SLWO, ofthe sterilization unit 570 and is fluidly coupled to conduit 582. Thediverter valve 638 represents another one of the “K” actuators of thesterilization unit 570, and is electrically connected to anotheractuator output of the PLC circuit 120 via another one of the “K” signalpaths 130 ₆. The PLC circuit 120 is configured to control operation ofthe diverter valve 638 to control the flow direction of the liquid wasteflowing through conduit 636. Under certain operating conditions, the PLCcircuit 120 is operable to control the diverter valve 638 to direct thebiomaterial waste stream exiting the post-sterilization heat exchangerHX1 back to the inlet of the liquid waste pump 612 for recirculation ofthe liquid waste through the sterilization unit 570. Otherwise, the PLCcircuit 120 is operable to control the diverter valve 638 to direct thebiomaterial waste stream out of the sterilization unit 570 and to thefermentation unit 580.

Yet another one of the “L” sensors included within the sterilizationunit 570 is a conventional outlet pressure sensor 122 ₈ disposed influid communication with conduit 642 between one outlet of the divertervalve 638 and the inlet of the pressure control valve 644, andelectrically connected to another sensor input of the PLC circuit 120via another of the “L” signal paths 124 ₈. The pressure sensor 122 ₈ isoperable to produce a signal on signal path 124 ₈ indicative of thepressure of the liquid biomaterial waste stream entering the inlet ofthe pressure control valve 644, which corresponds to the pressure of thebiomaterial waste stream within the sterilization unit 570. The pressurecontrol valve 644 represents yet another one of the “K” actuators of thesterilization unit 570, and is electrically connected to anotheractuator output of the PLC circuit 120 via another of the “K” signalpaths 130 ₆. The PLC circuit 120 is configured to control operation ofthe pressure control valve 644 by providing an appropriate actuatorcontrol signal on signal path 130 ₆ and based on the signal produced bythe pressure sensor 122 ₈ to maintain the liquid waste within thesterilization unit 570 near a desired liquid waste pressure.

Some of the conduits and butterfly valves just described are included toallow for the cleaning/sterilization of the sterilization unit 570. Forexample, in the cleaning/sterilization process described hereinabovewith respect to the pH adjustment unit 38, butterfly valves BVJ and BVHmay be closed and the butterfly valve BVI opened to provide acleaning/sterilization path back to the pH adjustment unit 38. Duringnormal, continuous flow operation of the sterilization unit 570, thebutterfly valves BVJ and BVH are opened and the butterfly valve BVH isclosed. Similarly, butterfly valve BVL may be closed and butterfly valveBVK may be opened to allow steam provided by the steam system 572 viaconduit to be supplied to conduit 614 for circulation throughout thesterilization unit 570 when the diverter valve 636 is controlled by thePLC 120 to recirculate the liquid, in this case water, flowing throughconduit 634 back through the pump 612 via conduits 638 and 610. Whensuch cleaning/sterilization is complete, the butterfly valve BVK may beclosed and the butterfly valve BVL opened to direct the liquidcirculating through the sterilization system 470 to the liquid wastereturn conduit 76 via butterfly valve BVL. During normal, continuousflow operation, the butterfly valves BVK and BVL are both closed. Inaddition to the manual butterfly valves just discussed, thesterilization unit 570 further includes a number of additional manualvalves as illustrated in FIG. 13A. Some of these manual valves are checkvalves, CV, that are positioned in a number of locations to ensureone-way liquid flow. Others of the manual valves are butterfly or ballvalves, BV, and are included within the sterilization unit 570 atvarious locations to allow for bypassing of, and maintenance orreplacement of, various components of the sterilization unit 570.

In another embodiment, a separation process is described where proteins,enzymes, peptides, and the like are removed from the biomaterial wastestream. This separation process may used as a stand-alone treatmentprocess, or as a component of a purification system, treatment system,or fermentation system, such as those described herein. In one aspect,the proteins, enzymes, peptides, and the like are removed by a processthat includes the steps of treating the biomaterial waste stream withheat, and removing the proteins, enzymes, peptides, and the like on thebasis of density. In another aspect, the heating step is adapted tocause the precipitation, polymerization, or aggregation of the proteins,enzymes, peptides, and the like to form higher molecular weightmaterials, larger particles, and/or higher density particles in thebiomaterial waste stream. Such higher molecular weight materials, largerparticles, and/or higher density particles may be removed from theheated biomaterial waste stream under natural gravity, or by means of agravity induced by for example Coriolis, centrifugal, and/or centripetalforces applied to the heated biomaterial waste stream.

In one variation of this separation process, a separation unit is addedin-line prior to sterilization unit. In another variation of theseparation process, a separation unit is positioned partway or as anintegral component of the sterilization unit. It is appreciated that therelative positioning of separation unit in sterilization unit may beadvantageously optimized to achieve a balance between heating time andseparation time. For example, separation unit may be placed near the endof sterilization unit to allow maximum heating of the biomaterial wastestream, allowing for maximum precipitation, polymerization, oraggregation of proteins, enzymes, peptides, and the like. It isunderstood that such an embodiment may require a longer sterilizationtime and/or higher sterilization temperatures due to the higher heatcapacity of a biomaterial waste stream that still includes suchproteins, enzymes, peptides, and the like. Alternatively, separationunit may be placed near the beginning of sterilization unit to allowearly removal of precipitated, polymerized, or aggregated proteins,enzymes, peptides, and the like. It is understood that such anembodiment may require a higher initial heating temperature toaccomplish the desired aggregation, but the sterilization time may beshorted due to the lower heat capacity of the pretreated biomaterialwaste stream after removal of the proteins, enzymes, peptides, and thelike. It is further appreciated that in this latter variation that earlyremoval will allow either shorter duration or lower temperaturesterilization steps. Such shorter duration or lower temperaturesterilization steps may have the added benefit of decreasing overallcosts of the processes described herein. In addition, such shorterduration or lower temperature sterilization steps may have the addedbenefit of preserving certain valuable nutrients useable by thefermenting organisms in systems that include fermentation processes,such as valuable organic molecules that might otherwise be degraded bylonger duration or higher temperature sterilization steps. For example,certain vitamins and certain carbohydrates may be destroyed insterilization procedures that include higher heat of sterilizationand/or prolonged sterilization times. Illustratively, lower heats and/orshorter times may be used to preserve nutrients such as biotin,pantothenic acid, niacins, B vitamins, including Vitamin B₁, Vitamin B₃,Vitamin B₅, Vitamin B₆, and/or Vitamin B₁₂.

Similarly, the foregoing description is equally applicable tobiomaterial waste streams that include vegetative cells, including liveor dead bacterial cells. Such cells may tend to cause longersterilization times and/or higher sterilization temperatures due to thehigher heat capacity of biomaterial waste streams that includevegetative cells. It is appreciated that removal of such cells mayshorten the time required, or lower the temperature required forsterilization. It is understood that the sterilization step desirablykills competing vegetative cells, and or spores that might compete fornutrients in the fermentation process and decrease overall yield orquality of product. However, the temperatures and or times required tokill cells are each typically greater than required to kill spores.Therefore, removal of vegetative cells either prior to or concurrentwith sterilization will allow shorter times and/or lower temperatures tobe used.

In another embodiment of the processes and apparatus described hereinfor fermentation, a sterilization step is included (see FIGS. 13A &13B). In one illustrative aspect, the sterilization step illustrativelyreduces the spore count of the biomaterial waste stream entering theprecipitating step by a factor of about 10⁶. In another illustrativeaspect, the spore count is reduced to a value from about 10⁸ per mL orgreater to a value of about 100 per mL or less. It is appreciated thatsuch reductions of spore counts include the substantial removal ofbacterial and other vegetative cells from the biomaterial waste streamentering the precipitating step as part of the pretreatment step. Inanother aspect, the particulate count, including the number ofvegetative, bacterial cells, and the like present in the biomaterialwaste stream entering the precipitating step is reduced by aprecipitating process, such as the precipitating processes describedherein, and illustratively shown in FIGS. 13B-13E.

It is understood that the sterilization rates of biomaterial wastestreams may follow a logarithmic profile, namely that the rate ofsterilization is first order with respect to the concentration ofmicroorganisms present in the biomaterial waste streams entering thesterilization step. In one aspect, the process of sterilization proceedsover a time period t according to the following equation$t = \frac{2.303 \cdot {\log\left( {N_{i}/N_{t}} \right)}}{K}$

where N_(t) is the number of organisms alive at time t, N_(i) is theinitial number of organisms, and K is the kinetic rate constant forparticular organism destruction. Illustratively spores of Bacillusstearothermophilus are used as an indicator for successful steamsterilization because of their high resistance to this type ofsterilization. Accordingly, sterilization processes described hereinthat are performed in a manner capable of achieving sterilization ofBacillus stearothermophilus are understood to be effective atsterilization of all or substantially all of other organisms present inbiomaterial waste stream. The values of K for Bacillusstearothermophilus at different sterilization temperature are listed inthe Table 1 TABLE 1 Calculated rate constant K as a function oftemperature for Bacillus stearothermophilus. Temperature K (° C.)(sec⁻¹) 100 0.000235 103 0.000457 106 0.00103 109 0.00209 112 0.00408115 0.00814 118 0.0162 121 0.0287 124 0.059 127 0.113 130 0.214 1330.400 135 0.742 139 1.36

Illustratively, a biomaterial waste stream that has been pretreatedusing the precipitating step described herein will be sterilized at afaster rate and/or at lower temperature that would be required for thebiomaterial waste stream entering the precipitating step. In one aspect,the biomaterial waste stream entering the precipitating step is barnwaste having an N_(i)=10⁶ spores/ml. In another aspect, the biomaterialwaste stream exiting the precipitating step is barn waste having anN_(i)=10² spore/ml. Illustratively, the predetermined maximum allowablespore count following sterilization is 1 spore per 1,000 gallons (3,800liters) of fermentation media, and the working volume of the fermenteris about 180,000 gallons (about 680,000 L). According to this aspect,the target spore count (N_(t)) alive at time t is or 2.64×10⁻⁷spores/mL. Using these values, the time required to achieve N_(t) fromN_(i) in this aspect as a function of temperature for biomaterial wastestream entering the precipitating step and for biomaterial waste streamexiting the precipitating step is shown in Table 2. TABLE 2 Comparisonof sterilization times at various temperatures for biomaterial wastestream entering or exiting a precipitating step. TemperatureSterilization time for Sterilization time for (° C.) entering waste(min.) exiting waste (min.) 100 2054 1401 103 1056 720 106 469 320 109231 158 112 118 80.7 115 59.3 40.4 118 29.8 20.3 121 16.8 11.5 124 8.185.58 127 4.27 2.91 130 2.26 1.54 133 1.21 0.82 135 0.65 0.44 139 0.360.24

Referring to Table 2, at each temperature, the time required forsterilizing the biomaterial waste stream exiting the precipitating stepis decreased by nearly 32% from the time required for sterilizing thebiomaterial waste stream entering the precipitating step.

It is appreciated that these processes may also convert a mediummolecular weight material, such as proteins, enzymes, peptides, and thelike in the range form about 10 kilo Daltons (kDa) to about 100 kDa intohigher molecular weight components by heating that may be removed asdescribed in separation unit. Subsequently, the removed high molecularweight components may be converted into low molecular weight componentsby acid degradation. Such low molecular weight components may benutrients whereas the starting medium molecular weight components arenot. Further, the resulting low molecular weight components may also notas readily precipitate, polymerize, or aggregate as the medium molecularweight components, and thus may be carried through sterilization stepsand into subsequent fermentation processes. It is further appreciatedthat such medium molecular weight components may also include dangerousor undesirable materials such as proteinaceous infective agents(prions).

Prions (Prion protein, PrP) is a small glycosylated protein that isabout 231 amino acids in length. The average molecular weight of thenaturally occurring amino acids is about 136; therefore, prions areexpected to have molecular weights in the range from about 20 kDa toabout 40 kDa, or about 31 kDa. In particular, PrP has been found to beresistant to even extremes of pH, heat, chemical degradation, andprotease degradation. Bovine Spongiform Encephalopathy (BSE) or Mad CowDisease is theorized to be an abnormal misfolding of this normal proteinto a highly β-sheet containing conformation. Therefore, the heattreating steps described herein are suitable for reducing the amount of,substantially removing, or in some cases completely removing suchmaterials. As described, the removed materials may be discarded oralternatively recycled into the system via an acid hydrolysis step. Itis understood that the acid hydrolysis step may not degrade prions tolow molecular weight components and therefore such precipitates may bediscarded. It is further understood that such components are desirablyremoved from certain products preparable from the processes describedherein, such as animal feed and animal feed supplement products.

In one illustrative embodiment of these processes, a system for treatinga biomaterial waste stream that includes a pretreatment step thatinvolves the precipitating step of selected components in thebiomaterial waste stream. In one variation of this precipitating step,other selected components remain part of the biomaterial waste streamfollowing the precipitating step. In one aspect, the precipitating stepprovides the precipitation, agglomeration, and/or aggregation,collectively referred to as precipitation, of proteins, proteinfragments, enzymes, enzyme fragments, and/or peptides, and the like. Inone variation, the proteins, protein fragments, enzymes, enzymefragments, and/or peptides having molecular weights of about 60 kDa orgreater, or in the range of molecular weights from about 20 kDa to about60 kDa, from about 20 kDa to about 40 kDa, from about 1 kDa to about 15kDa, or molecular weights of about 1 kDa or less. In another variation,the proteins, protein fragments, enzymes, enzyme fragments, and/orpeptides include prions. In another aspect, the precipitating stepprovides the precipitation, agglomeration, and/or aggregation ofparticulates, fine crystals, straw and bedding fragments, and the like.

In another aspect, the removed precipitated, polymerized, or aggregatedproteins, enzymes, peptides, and the like, and/or the vegetative cellsmay be subsequently sent to acid hydrolysis units for degradation.Following degradation, it is appreciated that the subsequent materialmay be a nutrient for fermenting organisms in the fermentation processesdescribed herein. Alternatively, the removed precipitated, polymerized,or aggregated proteins, enzymes, peptides, and the like, and/or thevegetative cells may be discarded, including those components thatcannot be otherwise degraded into smaller components by conventionalprocesses and apparatus, or by the processes and apparatus describedherein.

In another aspect, the pretreatment includes the step of heating thebiomaterial waste stream to cause the precipitation, polymerization, oraggregation of the proteins, enzymes, peptides, and the like, where thesubsequently precipitated, polymerized, or aggregated material alsotraps additional material, such as suspended particles, including clay,cells, fine straw particulates, bedding particulates, lignin, and thelike. The separation unit is configured to allow the aggregated materialto be removed on the basis of density either under natural gravity orunder an artificial gravity that is created by centrifugation,vortexing, or like process.

In another variation, metal salts are also added during the heating stepto facilitate precipitation, polymerization, and/or aggregation of thesuspended or dissolved material. Such metal salts include salts ofaluminum, iron, other transition metals, divalent and trivalent metals,and like salts. Counter anions of such metal salts include hydroxide,carbonate, biocarbonate, sulfate, bisulfate, chloride, bromide, and thelike.

In another variation, the removed aggregate material is recycled intoother separation processes and/or degradation processes describedherein, including acid hydrolysis processes. It is further appreciatedthat removing suspended or dissolved solids by precipitation asdescribed herein may reduce or prevent the clogging of optionaladditional apparatus such as filters, centrifuges, ultracentrifuges, andthe like.

In another embodiment, a system for treating a biomaterial waste streamthat includes this separation process and associated apparatus describedherein coupled to and feeding into a process and associated apparatusfor precipitating dissolved solids from an aqueous solution as describedherein. In one aspect of this embodiment, a fermentation step is alsoincluded. In another aspect of this embodiment, a fermentation step isnot included.

In one embodiment of the precipitating step, the precipitated,agglomerated, and/or aggregated, collectively referred to asprecipitated, components prepared in the precipitating step are removedby gravity settling. It is appreciated that in some configurations ofthe apparatus described herein, gravity settling may be unacceptablyslow due a chimney effect in the settling tank. It is furtherappreciated that gravity settling may be impracticable in continuousflow apparatus. It is understood that the chimney effect may be used tofacilitate settling of precipitated components prepared in theprecipitating step in configurations that involve continuous flow bycausing the precipitated components to collect and concentrate in adirection opposite to that of the clarified liquid component. In avertical configuration, the precipitated component may be directed tothe walls of a tank configured for performing the separating stepcreating thereby a downward flow. It is appreciated that in continuousflow configurations, the flow near the walls of the tank may be lower invelocity, allowing denser, or heavier particulate material to settle outof waste being treated, and leave a clarified liquid behind. It isfurther appreciated that due to heat loss at the walls of such tanks,settled particulates will tend to create a more pronounced downward flowdue to the increased density of the cooler settled material.

It is appreciated that substantial buffering of the biomaterial wastestream exiting the precipitating-separating step is removed whencomponents including proteins, bacterial cells, soluble fibers, andother components are removed from the biomaterial waste stream enteringthe precipitating-separating step. In system configurations that includeboth a precipitating-separation step and a post treatment step, it isappreciated that less base may be needed to raise the pH of thebiomaterial waste stream entering the post treatment step.

Referring now to FIG. 13B, a schematic diagram of another illustrativeembodiment of the sterilization unit 570′ and corresponding controlsystem that forms part of the waste fermentation system 14 is shown. Thesterilization unit 570′ and associated control system illustrated inFIG. 13B is identical in many respects to the sterilization unit 570 andassociated control system illustrated in FIG. 13A, and like numbers aretherefore used to identify like components. In the embodimentillustrated in FIG. 13B, a high pressure biomaterial waste settling tank637 is interposed between the waste stream outlet of the heat exchangerHX1 and the waste stream inlet of the heat exchanger HX2. Moreparticularly, the waste stream outlet of the heat exchanger HX1 isfluidly coupled to a waste stream inlet of the high pressure settlingtank 637 via a conduit 623 coupled to a conduit 635, and a waste streamoutlet of the high pressure settling tank 637 is fluidly coupled to thewaste stream inlet of the heat exchanger HX2 via a conduit 639. Aprecipitation initiation tank 633 has an outlet fluidly coupled to aninlet of a conventional pump 627 via a conduit 631. An outlet of thepump 627 is fluidly coupled to an inlet of a mixer 625 having an outletfluidly coupled to the junction of the conduits 623 and 635. Aconventional pump driver 629 is electrically connected to the pump 627,and is electrically connected to another actuator output of the PLCcircuit 120 via signal path 130 _(A). The precipitation initiation tank633 contains a precipitation initiator fluid or mixture, as will bedescribed in greater detail hereinafter, and the PLC circuit 120 isoperable to control the pump 465 to controllably provide theprecipitation initiator contained within the tank 633 to the waste inletof the high pressure settling tank 637.

A waste outlet of the high pressure settling tank 637 is fluidly coupledto an inlet of another conventional pump 643 via a conduit 641, and theoutlet of the pump 643 is fluidly coupled to an inlet of a control valve647. A conventional pump driver 645 is electrically connected to thepump 643, and is electrically connected to another actuator output ofthe PLC circuit 120 via signal path 130 _(B). The control input of thecontrol valve 647 is likewise electrically connected to another actuatoroutput of the PLC circuit 120 via signal path 130 _(C). The outlet ofthe control valve 647 is fluidly coupled to a waste inlet of a lowpressure settling tank 649 via a conduit 655, and a liquid outlet of thelow pressure settling tank 649 is fluidly coupled to the residual liquidoutlet 74 of the waste fermentation system 14. A waste outlet of the lowpressure settling tank 649 is fluidly coupled to an inlet of anotherconventional pump 651 via a conduit 657, and an outlet of the pump 651is fluidly coupled to the precipitated waste outlet conduit 80. Anotherconventional pump driver 653 is electrically connected to the pump 651,and is electrically connected to another actuator output of the PLCcircuit 120 via signal path 130 _(C).

Referring now to FIG. 13C, a cross-sectional view of either of thesettling tanks 637, 649 is shown. In the illustrated embodiment, thetank 637, 649 is cylindrically-shaped and has an outer wall 661terminating at a top 687 at one end, and terminating at a bottom 683 atan opposite end. The top 687 defines a liquid outlet in fluidcommunication with the conduit 639, 74, and the bottom 683 defines asolid waste outlet 685 fluidly coupled to the conduit 641, 657. A numberof inner cylinders 663 ₁-663 _(N) are positioned inside of the tank 637,649 and stacked one atop another, wherein N may be any positive integer.Referring to FIG. 13D, an illustrative embodiment of one of the innercylinders 663 is shown. The inner cylinder 663 is hollow and has an openbottom end 665 and an opposite end having a truncated cone top 667. Thetruncated cone top defines an opening 669 therethrough, and thetruncated cone top 667 slopes generally downwardly and away from theopening 669. A conical disk 671 is positioned approximately centrallywithin the inner cylinder 663, and is held in place by a suitable rod,plate or similar structure 673 secured to the wall of the inner cylinder663 and the conical disk 671. The conical disk 671 is positioned withinthe inner cylinder 663 approximately mid way between the bottom 665 andthe opening 669, with the tip of the cone extending generally toward acenter of the opening 669.

Referring again to FIG. 13C, the inner cylinders 663 ₁-663 _(N) arestacked one atop another, and the open bottom ends 665 ₁-665 _(N) aresized relative to the truncated cone tops 667 ₁-667 _(N) so thatadjacent bottoms and tops of the inner cylinders 663 ₁-663 _(N) formgaps 679 therebetween. It will be noted that the top-most inner cylinder663 _(N) does not have a truncated cone-top in the illustratedembodiment, and is instead open like the bottom end 665 _(N), althoughit will be understood that the top-most inner cylinder 663 _(N) mayalternatively include a truncated cone-top. A cone-shaped bottom member681 is positioned adjacent to the bottom 683 of the tank 637, 649, andis sized to form a gap 679 between the bottom 665 ₁ of the bottom-mostinner cylinder 663 ₁ and the bottom member 681 as illustrated in FIGS.13C and 13D. The bottom-most inner cylinder 6631 includes a secondconical disk 675 inverted relative to the conical disk 671 ₁ with theconical disk juxtaposed over the conical disk 675. the distal end 635A,655A of the waste inlet conduit 635, 655 is directed upwardly toward thetip of the conical disk 675.

In example one embodiment, the following dimensions apply to the innercylinders 663 ₁-663 _(N) and to the tank 637, 649, although it will beunderstood that the inner cylinders 663 ₁-663 _(N) and tank 637, 649 maybe constructed with other dimensions. Each of the inner cylinders 663₁-663 _(N), in this example, are 25 inches (64 cm) in height and 46inches (117 cm) in diameter. The openings 669 ₁-669 _(N) are 20 inches(51 cm) in diameter, and the conical disks 671 ₁-671 _(N) are 22 inches(56 cm) in diameter. The tank 637, 649 is 12 feet (3.7 m) in height, and4 feet (1.2 m) in diameter. The distance between the lowest edge of theconical disks 671 ₁-671 _(N) and the openings 669 ₂-669 _(N) above is15.5 inches (39.4 cm), and the distance between the lowest edge of theconical disks 671 ₂-671 _(N) and the openings 669 ₁-669 _(N−1) below is10 inches (25 cm). The size of the gaps 679 are ½ inch (1.3 cm), and thedistance between the center of the conduit 635, 655 and the bottom 665 ₁of the bottom-most inner cylinder 663 ₁ is 8 inches (20 cm). Thedistance between the distal end 635A, 655A of the conduit 635, 655 andthe tip of the conical disk 675 is 5 inches (13 cm), the distancebetween the distal end 635A, 655A of the conduit 635, 655 and the tip ofthe conical disk 671 ₁ is 10.5 inches (26.7 m), and the distance betweenthe distal end 635A, 655A of the conduit 635, 655 and the adjacent edgesof the of the conical disks 671 ₁ and 675 is 7.5 inches (19.1 cm). Thediameter of the waste outlet 685 is 1 foot (0.3 m), and the distancebetween the center of the conduit 641, 657 and the bottom of the wasteoutlet 685 is 3.5 inches (8.9 cm).

Referring now to FIGS. 13E and 13F, operation of the settling tanks 637,649, as it relates to the flow of liquid biomaterial waste therethroughand extraction of solids, will now be described. As shown in FIG. 13E,liquid biomaterial waste, which is periodically mixed with aprecipitation initiator from the precipitation initiator tank 633 asdescribed herein, enters the waste inlet 635, 655 as illustrated by thedirectional arrow 689. This liquid mixture exits the distal end 635A,655A of the waste inlet conduit 635, 655 and is directed toward the tipof the conical disk 675. As illustrated by the directional arrows 691,the conical disk 675 directs the liquid flow outwardly around theconical disks 675 and 671 ₁. Because the opening 669 ₁ is smaller indiameter than the conical disks 675 and 671 ₁, the flow of liquid isdirected back toward the center of the inner cylinder 663 ₁ as shown.This process repeats as the liquid travels upwardly through the tank635, 655. This liquid flow pattern causes the flow rate of liquidthrough the inner cylinders 663 ₁-663 _(N) to be greater toward centerof each of the inner cylinders 663 ₁-663 _(N) and less near the outerwalls of each of the inner cylinders 663 ₁-663 _(N). This is illustratedgraphically in FIG. 13F by the directional arrows 693A and 693B, whereinthe arrow 693B indicates a higher flow rate and the arrow 693A indicatesa relatively lesser flow rate. As a result of this liquid flow pattern,areas 695 of little or no liquid flow are created just above thetruncated cone tops 667 ₁-667 _(N) near the sidewalls of each of theinner cylinders 663 ₁-663 _(N). Heavier waste particles carried by thebiomaterial waste tend to drop out of the liquid in the low or no flowareas 695, and begin to collect on the truncated conical tops 671 ₁-671_(N). When sufficient amounts of waste particles have collected, thecollective weight of the waste particles cause them to slide off theconical tops 671 ₁-671 _(N), through the gaps 679, and downwardly towardthe bottom 683 of the tank 637, 649 as illustrated by the directionalarrows 697 and 699. In addition, it is appreciated that due to heat lossthrough the outer walls of tanks 637, 649, the liquid flowing in gap maybe cooler than the bulk liquid entering and exiting tanks 637, 649. Thiscooler liquid will be more dense, and will facilitate movement of solidwaste particles from low or no flow areas 695 into gaps 679, anddownwardly toward the bottom 683 of the tank 637, 649. The resultingsolid waste particles are collected in the waste outlet 685, asindicated by the directional arrows 701, and may be periodically pumpedout by periodically activating the waste pumps 643 and 651. The periodicoperation of the pumps 643 and/or 651 is, in one embodiment, time-based.Other pump control strategies may alternatively be used.

In one illustrative example, pre-fermentation barn flush liquid wastespiked with a 29 kDa protein was treated at pH 4, with added aluminum,and heated at 121° C. to remove proteins in the 20-40 kDa molecularweight range, and illustratively in the 27-32 kDa molecular weight range(understood to be the prion molecular weight range).

Operation of the sterilization unit 570 is controlled by the PLC circuit120 based on information provided by one or more of the sensorsassociated with the sterilization unit 570. Referring now to FIGS.14A-14C, a flowchart of one illustrative embodiment of a softwarealgorithm 650 for controlling the sterilization unit 570 is shown. Itwill be understood that the software algorithm 650 represents oneillustrative strategy for controlling the sterilization unit 570 duringnormal, continuous flow operation of the biomaterial waste processingsystem 10, and that the sterilization unit 570 may be controlleddifferently during other operational modes of the biomaterial wasteprocessing system 10. Examples of other operational modes of thebiomaterial waste processing system 10 may include, but are not limitedto, off, power/air fail, power/air fail recovery, seeding, start-up,transition from start-up to normal, continuous flow operation,preparation for system sterilization and system sterilization. In anycase, the software algorithm 650 is stored within, or programmed into,the PLC circuit 120, and the PLC circuit 120 is operable to executealgorithm 650 to control the operation of the sterilization unit 570.

The control algorithm 650 includes a number of different andindependently executing control routines, and each of these differentcontrol routines will be described separately. For example, the controlalgorithm 650 includes a first control routine 652 for controlling thespeed of the liquid waste pump 612 as a function of the inlet pressuresignal on signal path 124 ₄ to maintain the pressure of the biomaterialwaste stream entering the liquid waste pump 612 below a threshold inletpressure, and also as a function of the flow rate signal on signal path124 ₃ to maintain the flow rate of the biomaterial waste stream enteringthe liquid waste inlet port, LWI, of the sterilization unit 570 betweenupper and lower flow rate values. The control routine 652 begins at step654 where the PLC circuit 120 is operable to sense the waste streaminlet pressure, P_(I), by monitoring the inlet pressure signal on signalpath 124 ₄. Thereafter at step 656, the PLC circuit 120 is operable tocompare the waste stream inlet pressure, P_(I), to an inlet pressurethreshold, P_(ITH). If P_(I) exceeds P_(ITH) at step 656, execution ofthe control routine 652 advances to step 658 where the PLC circuit 120is operable to control the pump driver 616, by producing an appropriateactuator control on signal path 130 ₂, to reduce the pump speed of theliquid waste pump 612. If, on the other hand, the PLC circuit 120determines at step 656 that P_(I) is less than or equal to P_(ITH),execution of the control routine 652 advances to step 660 where the PLCcircuit 120 is operable to sense the waste stream inlet flow rate, FRI,by monitoring the flow rate signal on signal path 124 ₃. Thereafter atstep 662, the PLC circuit 120 is operable to compare the waste streaminlet flow rate, FRI, to a high flow rate threshold, FR_(HTH). If FRIexceeds FR_(HTH) at step 662, execution of the control routine 654advances to step 664 where the PLC circuit 120 is operable to controlthe pump driver 616, by producing an appropriate actuator control onsignal path 130 ₂, to reduce the pump speed of the liquid waste pump612. If, on the other hand, the PLC circuit 120 determines at step 662that FRI is less than FR_(HTH), execution of the control routine 652advances to step 666 where the PLC circuit 120 is operable to comparethe waste stream inlet flow rate, FRI, to a low flow rate threshold,FR_(LTH), wherein FR_(LTH)<FR_(HTH). If FRI is less than FR_(HTH) atstep 666, execution of the control routine 652 advances to step 668where the PLC circuit 120 is operable to control the pump driver 616, byproducing an appropriate actuator control on signal path 130 ₂, toincrease the pump speed of the liquid waste pump 612. If, on the otherhand, the PLC circuit 120 determines at step 666 that FRI is greaterthan or equal to FR_(LTH), execution of the control routine 652 loopsback to step 654, as it also does following steps 658, 664 and 668. ThePLC circuit 120 is thus operable, pursuant to control routine 652, tocontrol the speed of the liquid waste pump 612 to maintain the liquidpump inlet pressure below a pressure threshold, P_(ITH), and to maintainthe flow rate of the incoming waste stream to the sterilization unit 570within a flow rate window defined between lower and upper flow ratethresholds FR_(LTH) and FR_(HTH) respectively.

The sterilization unit control algorithm 650 further includes anothercontrol routine 670 for controlling the steam control valve 634 as afunction of the heat exchanger outlet temperature signal on signal path124 ₆ to maintain the temperature of the biomaterial waste streamexiting the pre-sterilization heat exchanger HX2 above a targetsterilization temperature. The control routine 670 begins at step 672where the PLC circuit 120 is operable to determine whether thesterilization unit 570 is enabled for operation. Generally, the PLCcircuit 120 is operable to command sterilization operation under normal,continuous flow operation, and in such an operation mode sterilizationis thus typically commanded. If, however, the PLC circuit 120 determinesat step 672 that sterilization operation is not currently commanded orenabled, execution of the control routine 670 advances to step 674 wherethe PLC circuit 120 is operable to control the position of the steamcontrol valve 634, by producing an appropriate actuator command signalon signal path 130 ₄, to a closed position. If, on the other hand, thePLC circuit 120 determines at step 672 that sterilization operation iscurrently commanded or enabled, the PLC circuit 120 is operable at step676 to sense the temperature of the waste stream exiting thepre-sterilization heat exchanger HX2, TEX, by monitoring the heatexchanger outlet temperature signal on signal path 124 ₆. Thereafter atstep 678, the PLC circuit 120 is operable to compare TEX to a targetsterilization temperature, TST. If TEX exceeds TST at step 678,execution of the control routine 670 advances to step 680 where the PLCcircuit 120 is operable to control the position of the steam controlvalve 634, by producing an appropriate actuator control signal on signalpath 130 ₄, to reduce TEX by decreasing the flow area through the steamcontrol valve 634. If, on the other hand, the PLC circuit 120 determinesat step 678 that TEX not greater than TST, execution of the controlroutine 670 advances to step 682 where the PLC circuit 120 is operableto again compare TEX to the target sterilization temperature, TST. IfTEX is less than TST at step 682, execution of the control routine 670advances to step 684 where the PLC circuit 120 is operable to controlthe position of the steam control valve 634, by producing an appropriateactuator control on signal path 130 ₄, to increase TEX by increasing theflow area through the steam control valve 634. Execution of the controlroutine 672 loops from the “no” branch of step 682 back to step 672, asit also does following steps 674, 680 and 684. The PLC circuit 120 isthus operable, pursuant to control routine 670, to control the positionof the steam control valve 634 to maintain the temperature of the wastestream exiting the pre-sterilization heat exchanger HX2 near a targetsterilization temperature, TST.

The sterilization unit control algorithm 650 further includes anothercontrol routine 686 for controlling operation of the diverter valve 638as a function of the sterilization outlet temperature signal on signalpath 124 ₇ to ensure the temperature of the biomaterial waste streamwithin the sterilization loop 630 is maintained near the targetsterilization temperature for a predefined sterilization time period.The control routine 686 begins at step 688 where the PLC circuit 120 isoperable to determine whether the sterilization unit 570 is enabled foroperation as described hereinabove. If the PLC circuit 120 determines atstep 688 that sterilization operation is not currently commanded orenabled, execution of the control routine 686 advances to step 696 wherethe PLC circuit 120 is operable to control the position of the divertervalve 638, by producing an appropriate actuator command signal on signalpath 130 ₅, to direct the biomaterial waste stream flowing throughconduit 636 to conduit 640 to thereby recirculate the waste stream backthrough the sterilization unit 570. If, on the other hand, the PLCcircuit 120 determines at step 688 that sterilization operation iscurrently commanded or enabled, the PLC circuit 120 is operable at step690 to sense the temperature, TSLO, of the waste stream exiting thesterilization loop 630 by monitoring the sterilization loop outlettemperature signal on signal path 124 ₇. Thereafter at step 692, the PLCcircuit 120 is operable to compare TSLO to the target sterilizationtemperature, TST. If TSLO is less than TST at step 692, execution of thecontrol routine 686 advances to step 696. If, on the other hand, the PLCcircuit 120 determines at step 692 that TSLO is greater than or equal toTST, execution of the control routine 686 advances to step 694 where thePLC circuit 120 is operable control the position of the diverter valve638, by producing an appropriate actuator command signal on signal path130 ₅, to direct the biomaterial waste stream flowing through conduit636 to conduit 642 to thereby route the sterilized waste stream to thepressure control valve 644. Execution of the control routine 686 loopsfrom either of steps 694 and 696 back to step 688. The PLC circuit 120is thus operable, pursuant to control routine 686, to control theposition of the diverter valve 638 to direct the waste stream exitingthe sterilization loop 630 back through the sterilization unit 570 ifthe temperature of the waste stream is below the target sterilizationtemperature, TST, and to otherwise direct the waste stream exiting thesterilization loop 630 to the pressure control valve 644.

The sterilization unit control algorithm 650 further includes anothercontrol routine 698 for controlling operation of the pressure controlvalve 644 as a function of the pressure of the biomaterial waste streamwithin the sterilization unit 570 to maintain the pressure of thebiomaterial waste stream within the sterilization unit 570 near a targetpressure value. The control routine 698 begins at step 700 where the PLCcircuit 120 is operable to sense the pressure, P_(S), of the wastestream within the sterilization system 570 by monitoring the outletpressure signal on signal path 124 ₈. Thereafter at step 702, the PLCcircuit 120 is operable to compare the pressure, P_(S), to a targetpressure value or pressure set point, P_(SET). If, P_(S) exceeds P_(SET)at step 702, execution of control routine 698 advances to step 704 wherethe PLC circuit 120 is operable to control the position of the pressurecontrol valve 644, by producing an appropriate actuator command signalon signal path 130 ₆, to reduce P_(S) by decreasing the flow areathrough the pressure control valve 644. If, on the other hand, the PLCcircuit 120 determines at step 702 that P_(S) is not greater thanP_(SET), execution of the control routine 698 advances to step 706 wherethe PLC circuit 120 is operable to compare P_(S) to a minimum wastestream pressure value, P_(MIN). Generally, it is desirable to setP_(MIN) to a pressure value slightly above which the pressure of thewaste stream within the sterilization unit 570 will drop if the safetypressure relief valve 619 opens to direct the biomaterial waste streamto the liquid waste return conduit 76. If, at step 706, the PLC circuit120 determines that P_(S) is less than P_(MIN), such as may occur if thesafety pressure relief valve 619 opens, execution of the control routine698 advances to step 708 where the PLC circuit 120 is operable tocontrol the position of the pressure control valve 644, by producing anappropriate actuator control on signal path 130 ₆, to close the controlvalve 644 and thereby inhibit the flow of the biomaterial waste streamto the sterilized liquid waste outlet, SLWO, of the sterilization unit570. If, on the other hand, the PLC circuit 120 determines at step 706that P_(S) is not less than P_(MIN), execution of the control routine698 advances to step 710 where the PLC circuit 120 is operable to againcompare P_(S) to P_(SET). If, at step 710, the PLC circuit 120determines that P_(S) is less than P_(SET), execution of the controlroutine 698 advances to step 712 where the PLC circuit 120 is operableto control the position of the pressure control valve 644, by producingan appropriate actuator command signal on signal path 130 ₆, to raisethe pressure, P_(S), of the waste stream within the sterilization system570. If, on the other hand, the PLC circuit 120 determines at step 710that P_(S) is not less than P_(SET), execution of the control routine698 loops back to step 700, as it also does following steps 704, 708 and712. The PLC circuit 120 is thus operable, pursuant to control routine698, to control the position of the pressure control valve 644 tomaintain the pressure of the waste stream within the sterilization unit570 near a target or set pressure value, P_(SET), and to close thepressure control valve 644 if the pressure of the waste stream withinthe sterilization system 570 drops below a minimum pressure value,P_(MIN).

The sterilization unit control algorithm 650 further includes anothercontrol routine 714 for controlling operation of the control valve 622between conduits 614 and 620 as a function of the pressure of thebiomaterial waste stream within the sterilization unit 570, when thesterilization unit 570 is operating in a recirculation mode with thediverter valve 638 directing the waste stream flowing through conduit636 to conduit 640, to prevent overpressure conditions. The controlroutine 714 begins at step 716 where the PLC circuit 120 is operable todetermine whether the sterilization unit 570 is operating in recycle orrecirculation mode. In the illustrated embodiment, the PLC circuit 120is configured to execute step 716 by monitoring the status of thediverter valve 638. For example, if the diverter valve 638 is positionedto direct the liquid waste stream to conduit 640, the sterilization unit570 is operating in recycle or recirculation mode, whereas if thediverter valve 638 is positioned to direct the liquid waste stream toconduit 642, the sterilization unit 570 is instead operating in thenormal, continuous flow mode. If the PLC circuit 120 determines at step716 that the sterilization unit 570 is not in recycle or recirculationmode, execution of the control routine 714 loops back for re-executionof step 716. If, on the other hand, the PLC circuit 120 determines atstep 716 that the sterilization unit 570 is in recycle or recirculationmode, execution of the control routine 714 advances to step 718 wherethe PLC circuit 120 is operable to sense the pressure, P_(R), of thewaste stream within the sterilization system 570 by monitoring theoutlet pressure signal on signal path 124 ₅. Thereafter at step 720, thePLC circuit 120 is operable to compare the pressure, P_(R), to athreshold pressure value, P_(RTH). If, P_(R) exceeds P_(RTH) at step720, execution of control routine 714 advances to step 722 where the PLCcircuit 120 is operable to control the position of the control valve622, by producing an appropriate actuator command signal on signal path130 ₃, to open the control valve 622. If, on the other hand, the PLCcircuit 120 determines at step 722 that P_(R) is not greater thanP_(RTH), execution of the control routine 698 advances to step 724 wherethe PLC circuit 120 is operable to control the position of the controlvalve 622, by producing an appropriate actuator command signal on signalpath 130 ₃, to close the control valve 622. Execution of the controlroutine 714 loops from either of steps 722 and 724 back to step 716. Inany operating mode of the sterilization unit 570, the mechanicalpressure relief valve 619 is configured to open if the pressure withinconduit 614 exceeds a safe operating pressure, P_(SAFE), to direct theflow of liquid waste through conduit 614 to the liquid waste returnconduit 76. Valve 622 and control routine 714 provide some redundancy inthis regard, and provide for more active control of the pressure of theliquid waste stream flowing through conduit 614.

EXAMPLE 1

Sterilization of an animal waste stream within the sterilization unit570 is achieved as a combination of time, temperature, and pH level ofthe waste stream. A relatively higher sterilization temperature willproduce a relatively shorter sterilization time. It has been found thatthe quality of the resulting sterilized animal waste stream is higherwith short duration sterilization times and concomitant highersterilization temperatures. An example of settings found effective aresummarized in Table 3: TABLE 3 Design Design Temperature PressureDescription (° F.) (° C.) (psig) Steam 320 160 75 Liquid enteringsterilization loop 630 275 135 31 Liquid exiting sterilization loop 630270 132.222 27 Liquid after sterilization ambient + 2-4 40 Pump pressurerequired 55

Sterilization Retention Time (TIMING LOOP 630): Sterilization loop pipediameter 6 inches (15.24 centimeters) Sterilization loop length 173 feet(52.7304 meters) Volume of loop 254 gallons (961.494 liters) Flow rateof Liquid 125 gpm (473.1771 pm) Retention time 2.03 minutesThe retention time at 100 gpm (379 lpm) is (125/100)*2.03=2.5 minutes

Referring now to FIG. 15, a schematic diagram of one illustrativeembodiment of the steam unit 572 forming part of the waste fermentationsystem, 14 of FIG. 12 is shown. In the illustrated embodiment, the waterinlet, WI, of the steam unit 572 is fluidly coupled to the water inletconduit 66, and also to a water inlet conduit 730 coupled to an inlet ofa boiler feed surge tank 732 via a conventional control valve 734 and abutterfly valve, BV. The control valve 734 represents one of the “M”actuators of the steam unit 572, and is electrically connected to anactuator output of the PLC circuit 120 via one of the “M” signal paths130 ₇. The PLC circuit 120 is configured to control operation of thecontrol valve 734 by providing an appropriate actuator control signal onsignal path 130 ₇. One of the “N” sensors included within the steam unit572 is a conventional pressure sensor 122 ₉ disposed in fluidcommunication with the boiler feed surge tank 732, and electricallyconnected to the PLC circuit 120 via one of the “N” signal paths 124 ₉.The pressure sensor 122 ₉ is operable to produce pressure signal onsignal path 124 ₉ indicative of the water pressure within the boilerfeed surge tank 732, and the PLC circuit 120 is configured to processthe pressure signal in a known manner and determine a water level valuecorresponding to the level of water within the boiler feed surge tank732.

The chemical inlet port, CHI, of the steam unit 572 is fluidly coupledto the chemical inlet conduit 54, and is coupled to a chemical inlet ofthe boiler feed surge tank 732 via a conventional control valve 738 anda butterfly valve, BV, disposed in-line with a conduit 736. The controlvalve 738 represents another one of the “M” actuators of the steam unit572, and is electrically connected to an actuator output of the PLCcircuit 120 via another one of the “M” signal paths 130 ₈. The PLCcircuit 120 is configured to control operation of the control valve 738by providing an appropriate actuator control signal on signal path 130₈. The drain outlet, D, of the steam unit 572 is fluidly coupled to theliquid waste return conduit, 76, of the waste fermentation system 14,and is fluidly coupled through a butterfly valve, BV, to a drain outletof the boiler feed surge tank 732. Optionally, the butterfly valve, BV,may be replaced by a control valve that is electrically controlled bythe PLC circuit 120. In this embodiment, the boiler feed surge tank 732may thus be drained under the control of the PLC circuit 120. The boilerfeed surge tank 732 is configured to store a quantity of pressurizedwater therein, and conventional water conditioning; e.g., watersoftening, chemicals may be provided to the boiler feed surge tank 732via the chemical inlet, CHI, to condition/soften the water storedtherein. It will be understood that in embodiments of the biomaterialwaste processing system 10 that include a source of conditioned water,such as the water source 24 illustrated in FIG. 11, the water suppliedto the boiler feed surge tank 732 via the water inlet, WI, of the steamunit 572 will be soft water. In such embodiments, the steam unit 572need not include the chemical inlet, CHI, control valve 738 andassociated butterfly valve, BV, and conduit 736, although thesecomponents may be included within the steam unit 572 to provide forfurther water conditioning control.

A water outlet of the boiler feed surge tank 734 is fluidly coupledthrough a pair of butterfly valves, BV, to a fresh water inlet of ade-aeration tank 742 via a conduit 740. A water outlet of thede-aeration tank 742 is fluidly coupled through a pair of flow reducersin the form of globe valves, GV, to a water inlet of a conventionalboiler 746. The de-aeration tank 742 is operable in a known manner topurge the water stored therein of air bubbles to minimize corrosion ofthe boiler 746 by oxygen carried by any such air bubbles. Although notshown in FIG. 15, the de-aeration tank 742 and boiler 746 include aconventional closed-loop feedback system therebetween that is notcontrolled by the PLC circuit 120, and that maintains the boiler 746 ata desired pressure/temperature.

A steam/water return inlet of the de-aeration tank 742 is fluidlycoupled through a flow reducer in the form of a globe valve, GV, to anoutlet of a conventional steam trap 750 via a steam return conduit 748,and an inlet of the steam trap 750 is fluidly coupled to an outlet of aconventional particle strainer 752. An inlet of the particle strainer752 defines the sterilization steam inlet port, SSTI, of the steam unit572 and is fluidly coupled to conduit 576. The steam return conduit 748is further fluidly coupled via another globe valve, GV, and a checkvalve, CV, to an outlet of another conventional steam trap 756 via aconduit 754. An inlet of the steam trap 756 is fluidly coupled to anoutlet of another conventional particle strainer 758 having an inletdefining the pasteurization steam inlet port, PSTI, of the steam unit572 and is fluidly coupled to conduit 602.

The steam outlet conduit 760 fluidly coupled to the steam outlet of theboiler 746 defines the sterilization steam outlet, SSTO, thepasteurization steam outlet, PSTO, and the steam outlet, ST, to the airsystem 56, of the steam system 572, and is accordingly fluidly connectedto conduits 574 and 604, and 64. The steam outlet conduit 760 is furtherfluidly coupled to a cleaning steam conduit 762 that is fluidly coupledto the cleaning steam outlet, CSO, of the steam unit 572, and thereforeto conduit 578, through a pair of flow reducers in the form of globevalves, GV. The steam outlet conduit 760 is also fluidly coupled to asample cleaning steam conduit 764 that is fluidly coupled to the samplecleaning steam outlet, SCSO, of the steam unit 572, and therefore toconduit 606, through another pair of flow reducers in the form of globevalves, GV. The boiler feed surge tank 732 is configured to supply waterto the de-aeration and boiler tanks 742 and 746 respectively, and theboiler tank 746 is configured to heat the water supplied thereto toproduce steam that is circulated through various other units of thewaste fermentation system 14 and air system 56 and then returned to thede-aeration and boiler tanks 742 and 746 for reheating. A number ofbutterfly valves, BV, and globe valves, GV, are included within thesteam unit 572 at various locations to allow for bypassing of, andmaintenance or replacement of, various components of the steam unit 572.The globe valves, GV, also provide for predefined pressure or flowreductions of the steam or water across these valves.

Referring now to FIG. 16, a flowchart of one illustrative embodiment ofa software algorithm 770 for controlling the steam unit 572 is shown. Itwill be understood that the software algorithm 770 represents oneillustrative strategy for controlling the steam unit 572 during normal,continuous flow operation of the biomaterial waste processing system 10,and that the steam unit 572 may or may not be controlled differentlyduring other operational modes of the biomaterial waste processingsystem 10. In any case, the software algorithm 770 is stored within, orprogrammed into, the PLC circuit 120, and the PLC circuit 120 isoperable to execute algorithm 770 to control operation of the steam unit572. The algorithm 770 begins at step 772 where the PLC circuit 120 isoperable to determine the water level, L_(BF), in the boiler feed surgetank 732. In the illustrated embodiment, the PLC circuit 120 is operableto execute step 772 by monitoring the signal produced by the pressuresensor 122 ₉ on signal path 124 ₉, and processing this signal in a knownmanner to determine L_(BF). Thereafter at step 774, the PLC circuit 120is operable to compare L_(BF) to a threshold water level, L_(TH). IfL_(BF) is less than L_(TH), execution of the algorithm 770 advances tostep 776 where the PLC circuit 120 is operable to control the waterinlet valve 734, by producing an appropriate control signal on signalpath 130 ₇, to open the water inlet valve 732. In one embodiment of thesteam unit 572, water conditioning chemicals are automatically addedwhenever the water inlet valve 732 is opened. In this embodiment,algorithm 770 includes optional step 778 as shown in phantom in FIG. 16.If included, the PLC circuit 120 is operable at step 778 to control thechemical inlet valve 738, by producing an appropriate control signal onsignal path 130 ₈, to open the chemical inlet valve 738. In alternativeembodiments, water conditioning chemicals are added on a timed or otherbasis, or not at all, and in these embodiments the optional step 778 maybe omitted. Algorithm execution loops from step 778, or from step 776 inembodiments where step 778 is not included in algorithm 770, back tostep 772.

If, at step 774, the PLC circuit 120 determines that L_(BF) is greaterthan or equal to L_(TH), algorithm execution advances to step 780 wherethe PLC circuit 120 is operable to control the water inlet valve 734, byproducing an appropriate control signal on signal path 130 ₇ to closethe water valve 734. In embodiments of the algorithm 770 including step778, algorithm 770 further includes the optional step 782 shown inphantom. If included, the PLC circuit 120 is operable at step 782 tocontrol the chemical inlet valve 738, by producing an appropriatecontrol signal on signal path 130 ₈, to close the chemical inlet valve738. Algorithm execution loops from step 782, or from step 780 inembodiments where step 782 is not included in algorithm 770, back tostep 772.

Referring now to FIG. 17, a schematic diagram of one illustrativeembodiment of the cooling tower unit 586 and corresponding controlsystem that forms part of the waste fermentation system 14 of FIG. 12 isshown. In the illustrated embodiment, the cooling fluid inlet, CFI thatis fluidly coupled to conduit 588 is also fluidly coupled through abutterfly valve, BV, to a cooling fluid inlet of a cooling tower 790. Aconventional fan motor 792 drives a cooling fan associated with thecooling tower 790, and is electrically connected to a conventional motordriver 794. The motor driver 794 represents one of the “I” actuators ofthe cooling tower unit 586, and is electrically connected to another oneof the actuator outputs of the PLC circuit 120 via one of the “I” signalpaths 130 ₉. The cooling tower 790 is a conventional water cooling unitconfigured to cool water flowing therethrough via operation of itscooling fan, and the PLC circuit 120 is operable to control the rate ofsuch cooling by controlling the fan motor 792 via the motor driver 794.

A fluid outlet of the cooling tower 790 is fluidly coupled to a coolingtower surge tank 798 via a conduit 796. One of the “J” sensors includedwithin the cooling tower unit 586 is a conventional temperature sensor122 ₁₁ disposed in fluid communication with the conduit 796 andelectrically connected to the PLC circuit 120 via one of the “J” signalpaths 124 ₁₁. The temperature sensor 122 ₁₁ is operable to produce atemperature signal on signal path 124 ₁₁ indicative of the temperatureof the water flowing through the conduit 796. Another one of the “J”sensors included within the cooling tower unit 586 is a conventionalpressure sensor 122 ₁₀ disposed in fluid communication with the coolingtower surge tank 798, and electrically connected to the PLC circuit 120via one of the “J” signal paths 124 ₁₀. The pressure sensor 122 ₁₀ isoperable to produce a pressure signal on signal path 124 ₁₀ indicativeof the water pressure within the cooling tower surge tank 798, and thePLC circuit 120 is configured to process this pressure signal in a knownmanner and determine a water level value corresponding to the level ofwater within the cooling tower surge tank 798. The cooling tower surgetank 798 further includes a fresh water inlet coupled through an inletcontrol valve 800 to the water inlet, WI, of the cooling tower unit 586,which is fluidly coupled to the water inlet conduit 26. The inletcontrol valve 800 represents another one of the “I” actuators of thecooling tower unit 586, and is electrically connected to another one ofthe actuator outputs of the PLC circuit 120 via one of the “I” signalpaths 130 ₁₀. The cooling tower surge tank 798 is a conventional waterstorage tank configured to store and controllably supply pressurizedwater.

The chemical inlet port, CHI, of the cooling tower unit 586 is fluidlycoupled to the chemical inlet conduit 54, and is coupled to a chemicalinlet of the cooling tower surge tank 798 via a conventional controlvalve 802 and a butterfly valve, BV. The control valve 802 representsanother one of the “I” actuators of the cooling tower unit 598, and iselectrically connected to another one of the actuator outputs of the PLCcircuit 120 via one of the “I” signal paths 130 ₁₁. The PLC circuit 120is configured to control operation of the control valve 802 by providingan appropriate actuator control signal on signal path 130 ₁₁.Conventional water conditioning; e.g., water softening, chemicals may beprovided to the cooling tower surge tank 798 via the chemical inlet,CHI, to condition/soften the water stored therein. It will be understoodthat in embodiments of the biomaterial waste processing system 10 thatinclude a source of conditioned water, such as the water source 24illustrated in FIG. 11, the fresh water supplied to the cooling towersurge tank 798 via the water inlet, WI, of the cooling tower unit 586will be soft water. In such embodiments, the cooling tower unit 586 neednot include the chemical inlet, CHI, and control valve 802, althoughthese components may be included within the cooling tower unit 586 toprovide for further control of the condition of the water stored in thecooling tower surge tank 798. In embodiments of the biomaterial wasteprocessing system 10 that do not include a source of fresh, conditionedwater, and the fresh water supplied to the water inlet, WI, of thecooling tower unit 586 is therefore unconditioned water, the coolingtower unit 586 may further include conventional water conditioningcomponents to condition the fresh water supplied to the cooling towersurge tank 798. In such embodiments, the water inlet, WI, of the coolingtower unit may be fluidly coupled to a conventional water conditioner,and the water conditioner fluidly coupled to the fresh water inlet ofthe cooling tower surge tank. The chemical inlet, CHI, in suchembodiments may be coupled to a chemical inlet of the water conditionerand/or cooling tower surge tank 798.

The cooling tower surge tank 798 further includes an overflow outletfluidly coupled to conduit 598 via the overflow outlet, OF, of thecooling tower unit 586. In embodiments of the biomaterial wasteprocessing system 10 including a source of conditioned water, such asthe water source 24 illustrated in FIG. 11, the overflow conduit 558 maybe fluidly coupled to such a water source to recirculate overflow waterthrough the water source 24. If, on the other hand, the biomaterialwaste processing system 10 does not include a water source such as watersource 24, but is instead configured to receive tap water from aconventional tap water source, the overflow conduit 558 may be fluidlycoupled to a suitable container, another water processing system orvented to ground. Alternatively, in such embodiments wherein the coolingtower unit 586 includes water conditioning components as just described,the overflow outlet of the cooling tower surge tank 798 may be fluidlycoupled to such water conditioning components.

The cooling tower surge tank 798 further includes a cooling fluid outletfluidly coupled through a butterfly valve, BV, to the cooling fluidoutlet, CFO, of the cooling tower unit 586 and also to conduit 590.Between the cooling fluid outlet of the cooling tower surge tank 798 andthe butterfly valve, BV, another conduit 804 is coupled through anoutlet control valve 806 to the drain outlet, D, of the cooling towerunit 586, which is fluidly coupled to conduit 592. The outlet controlvalve 806 represents another one of the “I” actuators of the coolingtower unit 586, and is electrically connected to another one of theactuator outputs of the PLC circuit 120 via another one of the “I”signal paths 130 ₁₂. The conditioned water stored in the cooling towersurge tank 798 may, over time, become saturated with water conditioningchemicals, and the PLC circuit 120 is configured to control the outletvalve 806 to periodically drain some of the saturated water from thetank 798 so that appropriate water conditioning chemical levels may berestored.

Another one of the “J” sensors included within the cooling tower unit586 is a conventional relative humidity sensor 122 ₁₂ disposed in fluidcommunication with the ambient air surrounding the cooling tower 790,and electrically connected to the PLC circuit 120 via one of the “J”signal paths 124 ₁₂. The relative humidity sensor 122 ₁₂ is operable toproduce a signal on signal path 124 ₁₂ indicative of the relativehumidity of the ambient air about the cooling tower 790. Yet another oneof the “J” sensors included within the cooling tower unit 586 is anotherconventional temperature sensor 122 ₁₃ disposed in fluid communicationwith the ambient air about the cooling tower 790, and electricallyconnected to the PLC circuit 120 via one of the “J” signal paths 124 ₁₃.The temperature sensor 122 ₁₃ is operable to produce a temperaturesignal on signal path 124 ₁₃ indicative of the temperature of theambient air surrounding the cooling tower 790. The PLC circuit 120 isconfigured to process the signals produced by the sensors 122 ₁₂ and 122₁₃ in a known manner to determine a dew point of the ambient airsurrounding the cooling tower 790, and to control operation of the fanmotor 792 as a function of the computed dew point.

The cooling tower unit 586 just described includes a number of manuallyactuated bufferfly valves, BV, as illustrated in FIG. 17. Such valvesare included within the cooling tower unit 586 at various locations toallow for bypassing of, and maintenance or replacement of, variouscomponents of the cooling tower unit 586.

Referring now to FIGS. 18A-18B, a flowchart of one illustrativeembodiment of a software algorithm 810 for controlling the cooling towerunit of FIG. 17 is shown. It will be understood that the softwarealgorithm 810 represents one illustrative strategy for controlling thecooling tower unit 586 during normal, continuous flow operation of thebiomaterial waste processing system 10, and that the cooling tower unit586 may be controlled differently during other operational modes of thebiomaterial waste processing system 10. The software algorithm 810includes a number of different and independently executing controlroutines, and each of these different control routines will be describedseparately. For example, the control algorithm 810 includes a firstcontrol routine 812 for controlling the level and condition of the waterin the cooling tower surge tank 798. The control routine 812 begins atstep 814 where the PLC circuit 120 is operable to determine the waterlevel, L_(CTS), in the cooling tower surge tank 798. In the illustratedembodiment, the PLC circuit 120 is operable to execute step 814 bymonitoring the signal produced by the pressure sensor 122 ₁₀ on signalpath 124 ₁₀, and processing this signal in a known manner to determineL_(CTS). Thereafter at step 816, the PLC circuit 120 is operable tocompare L_(CTS) to a threshold water level, L_(TH). If L_(CTS) is lessthan L_(TH), execution of the control routine 812 advances to step 818where the PLC circuit 120 is operable to control the water inlet valve800, by producing an appropriate control signal on signal path 130 ₁₀,to open the water inlet valve 800. Thereafter at step 820, the PLCcircuit 120 is operable to control the chemical inlet valve 802, byproducing an appropriate control signal on signal path 130 ₁₁, to openthe chemical inlet valve 802. Alternatively, the PLC circuit 120 may beconfigured to control the chemical inlet valve 802 on a timed or otherbasis, in which case step 820 may be omitted from the control routine812. Algorithm execution loops from step 820, or from step 818 inembodiments where step 820 is not included in control routine 812, backto step 814.

If, at step 816, the PLC circuit 120 determines that L_(CTS) is greaterthan or equal to L_(TH), execution of the control routine 812 advancesto step 822 where the PLC circuit 120 is operable to control the waterinlet valve 800, by producing an appropriate control signal on signalpath 130 ₁₀ to close the water valve 800. In embodiments of the controlroutine 812 including step 820, control routine 812 further includesstep 824 where the PLC circuit 120 is operable to control the chemicalinlet valve 802, by producing an appropriate control signal on signalpath 130 ₁₁, to close the chemical inlet valve 802. Execution of thecontrol routine 812 loops from step 824, or from step 822 in embodimentswhere step 824 is not included in control routine 812, back to step 814.

The cooling tower unit control algorithm 810 further includes anothercontrol routine 830 for controlling operation of the drain control valve806. The control routine 830 begins at step 832 where the PLC circuit120 is operable to monitor the status of a drain timer resident in thePLC circuit 120. Thereafter at step 834, the PLC circuit 120 is operableto determine whether the drain timer has timed out. If not, execution ofthe control routine loops back to step 832. If, however, the PLC circuit120 determines at step 834 that the drain timer has timed out, executionof the control routine 830 advances to step 836 where the PLC circuit isoperable to control the drain control valve 806 by opening the draincontrol valve 806 for a time period TD to drain a desired quantity ofwater from the cooling tower surge tank 798, and then to close the draincontrol valve 806. Thereafter at step 838, the PLC circuit 120 isoperable to reset the drain timer, and execution of the control routine830 loops from step 838 back to step 832.

The cooling tower unit control algorithm 810 further includes anothercontrol routine 840 for controlling operation of the fan motor 792. Thecontrol routine 840 begins at step 842 where the PLC circuit 120 isoperable to determine the relative humidity, RH, of the ambient airsurrounding the cooling tower 790. In the illustrated embodiment, thePLC circuit 120 is operable to execute step 842 by monitoring the signalproduced by the ambient relative humidity sensor 122 ₁₂ on signal path124 ₁₂. Thereafter at step 844, the PLC circuit 120 is operable todetermine the temperature, AT, of the ambient air surrounding thecooling tower 790. In the illustrated embodiment, the PLC circuit 120 isoperable to execute step 844 by monitoring the signal produced by theambient temperature sensor 122 ₁₃ on signal path 124 ₁₃. Following step844, the PLC circuit 120 is operable at step 846 to calculate the dewpoint temperature, T_(DP), as a known function of RH and AT.

Following step 846, the PLC circuit 120 is operable at step 848 todetermine the temperature, T_(C), of the water supplied by the coolingtower 790 to the cooling tower surge tank 798. In the illustratedembodiment, the PLC circuit 120 is operable to execute step 848 bymonitoring the signal produced by the temperature sensor 122 ₁₁ onsignal path 124 ₁₁. Thereafter at step 850, the PLC circuit 120 isoperable to compare the temperature, T_(C), of the water supplied by thecooling tower 790 to the cooling tower surge tank 798 with the dew pointtemperature, T_(DP). If T_(C) is less than or equal to T_(DP) at step850, then the cooling fan motor 792 is working harder than it needs toand execution of the control routine 840 advances to step 852 where thePLC circuit 120 is operable to control the motor driver 794 by producingan appropriate motor driver control signal on signal path 130 ₉, todecrease the speed of the fan motor 792 and therefore decrease the speedof the cooling tower fan. Execution of the control routine 840 loopsfrom step 852 back to step 842.

If, at step 850, the PLC circuit determines that T_(C)>T_(DP), executionof the control routine 840 advances to step 854 where the PLC circuit120 is operable to monitor the signal produced by the temperature sensor122 ₁₁ on signal path 124 ₁₁ over a predefined time period to determinethe change in T_(C), or ΔT_(C), over the predefined time period.Thereafter at step 856, the PLC circuit 120 is operable to compareΔT_(C) to a threshold temperature, T_(TH). If, at step 856,ΔT_(C)>T_(TH), then the cooling fan motor is not working hard enough andexecution of the control routine 840 advances to step 858 where the PLCcircuit 120 is operable to control the motor driver 794 by producing anappropriate motor driver control signal on signal path 130 ₉, toincrease the speed of the fan motor 792 and therefore increase the speedof the cooling tower fan. If, however, the PLC circuit 120 determines atstep 856 that ΔT_(C) is less than or equal to T_(TH), then any increasein the cooling tower fan speed will not correspondingly decrease T_(C)and execution of the control routine 840 advances to step 860 where thePLC circuit 120 is operable to control the motor driver 794 by producingan appropriate motor driver control signal on signal path 130 ₉, tomaintain the current speed of the fan motor 792 and therefore maintainthe current speed of the cooling tower fan. Execution of the controlroutine 840 loops from steps 858 and 860 back to step 842.

Referring now to FIG. 19, a diagrammatic representation of oneillustrative embodiment of the fermentation unit 580 forming part of thewaste fermentation system 14 of FIG. 12 is shown. In the illustratedembodiment, the fermentation unit 580 includes a first fermenter 870having a reactor 872 in the form of an elongated, hollow cylinder,although other geometric shapes of the reactor 872 are contemplated. Inthe illustrated embodiment, an elongated, hollow bottom inner cylinder874 is longitudinally received within the reactor 872 with a bottom end876 positioned adjacent to a bottom end 878 of the reactor, and a topend 880, and with the sidewall of the bottom inner cylinder 874positioned adjacent to and spaced apart from the sidewall of the reactor872. A hollow top inner cylinder 884 is also received within the reactor872 with a bottom end 882 positioned adjacent to and spaced apart fromthe top end 880 of the bottom inner cylinder 874, and a top end 886positioned adjacent to a top end 888 of the reactor 872, and with thesidewall of the top inner cylinder 884 positioned adjacent to and spacedapart from the sidewall of the reactor 872. A liquid outlet conduit 900is fluidly coupled to the reactor 872 adjacent to the sidewall of thetop inner cylinder 884, and an air outlet conduit 902 is fluidly coupledto the reactor 872 through the top end 888 of the reactor 872.

The reactor 872 further includes a funnel-shaped cone 890 positionedadjacent to the bottom end 876 of the bottom inner cylinder 874 andfluidly coupled to a product outlet conduit 892 extending from thebottom of the cone 890, and extending outwardly from the bottom end 878of the reactor 872. Fermenting organism formed in the first fermenter870 is extracted via the product outlet conduit 892. A liquid wasteinlet, LWI, is fluidly coupled via conduit 894 to the interior of thebottom inner cylinder 874 adjacent to the bottom end 876, and isconfigured to receive therein a continuous stream of liquid biomaterialwaste. A primary air inlet, F1O, is fluidly coupled to an outer airsparger 896 configured to distribute incoming air evenly about the cone890 within the bottom inner cylinder 874, and a secondary air inlet 898,F1I, is fluidly coupled to an inner air sparger 898 configured todistribute incoming air evenly within the interior of the cone 890.

The fermentation unit 580 further includes a second fermenter 910fluidly coupled to the first fermenter 870. The second fermenter 910 isdiagrammatically similar to the first fermenter 870 and includes areactor 912 in the form of an elongated, hollow cylinder, although othergeometric shapes and relative proportions of the reactor 912 than thoseillustrated are contemplated. In the illustrated embodiment, anelongated, hollow bottom inner cylinder 914 is longitudinally receivedwithin the reactor 912 with a bottom end 916 positioned adjacent to abottom end 918 of the reactor, and a top end 920, and with the sidewallof the bottom inner cylinder 914 positioned adjacent to and spaced apartfrom the sidewall of the reactor 912. A hollow top inner cylinder 924 isalso received within the reactor 912 with a bottom end 922 positionedadjacent to and spaced apart from the top end 920 of the bottom innercylinder 914, and a top end 926 positioned adjacent to a top end 928 ofthe reactor 912, and with the sidewall of the top inner cylinder 924positioned adjacent to and spaced apart from the sidewall of the reactor912. A liquid outlet conduit 936 is fluidly coupled to the reactor 912adjacent to the sidewall of the top inner cylinder 924, and is fluidlycoupled to the residual liquid outlet, RLO, of the fermentation unit580. An air outlet conduit 938 is fluidly coupled to the reactor 912through the top end 928 of the reactor 912, and is fluidly coupled tothe gas outlet, GO, of the fermentation unit 580.

The reactor 912 further includes a funnel-shaped cone 930 positionedadjacent to the bottom end 916 of the bottom inner cylinder 914 andfluidly coupled to a product outlet conduit 932 extending from thebottom of the cone 930, and extending outwardly from the bottom end 918of the reactor 912. The product outlet conduit 932 is fluidly coupled tothe product outlet, POF, of the fermentation unit 580. The productoutlet conduit 892 of the first fermenter unit 870 is fluidly coupled tothe lower portion of the cone 930 such that the fermenting organismextracted from the lower portion of the cone 890 of the fermenter 870enters the lower portion of the cone 930 of the fermenter 910, below theinner air sparger 934. The liquid outlet conduit 900 of the firstfermenter 870 is fluidly coupled to the interior of the bottom innercylinder 914 adjacent to the bottom end 916, and conduit 900 thus formsthe liquid waste inlet to the second fermenter 912 receiving therein acontinuous stream of liquid exiting the first fermenter 870. The airoutlet conduit 902 of the first fermenter 870 is fluidly coupled to anouter air sparger 904 configured to distribute incoming air evenly aboutthe cone 930 within the bottom inner cylinder 916, conduit 902 thusforms the primary air inlet to the second fermenter 910. A secondary airinlet, F2I, is fluidly coupled to an inner air sparger 934 configured todistribute incoming air evenly within the interior of the cone 930.

The fermenters 870, 910 illustrated in FIG. 19 represent an “air-lift”design, wherein mixing is performed by the introduction of air into theinner bottom cylinders 874, 914 and taking advantage of the circulationcreated as the result of the expansion of the air as it rises in thereactor 872, 912. This air is introduced into the reactors 872, 912 viathe outer air spargers 896, 904. Secondary air is selectively introducedwithin the cones 890, 930 via the inner air spargers 898, 934 to causeadmixing of the cone contents with the reactor contents. Admixing isprecluded when no secondary air flows through the inner air spargers898, 934. Exhaust gases are constantly and controllably removed from thesecond fermenter 910 via conduit 939 to maintain a constant desiredpressure within the fermenters 870, 910, and a constant volume of liquidis controllably removed via conduit 936 to maintain a constant desiredliquid volume within the fermenters 870, 910. Flocculated fermentingorganism is selectively removed from the first and second fermenters870, 910 to adjust the fermenting organism content in the correspondingreactors 872, 912.

In general, region “A” illustrated in FIG. 19 represents the region ofthe fermenters 870, 910 where air and liquid are separated, region “B”represents the region where liquid/air mixing and fermenting organismgrowth occurs, and region “C” represents the region where fermentingorganism reduction and separation is carried out. Details relating toeach of these operational regions of the fermenters 870, 910 will now bedescribed with respect to FIGS. 20-22, wherein FIG. 20 is a diagrammaticillustration of the general operation of either of the fermentationtanks 870, 910 in a normal, continuous flow operational mode, FIG. 21 isa diagrammatic illustration of the operation of the air spargers 896,898 and 904,930 and fermenting organism collection cone 890, 930 ineither of the fermentation tanks 870, 910 in a fermenting organismreduction operational mode, and FIG. 22 is a diagrammatic illustrationof the operation of the air spargers 896, 898 and 904,930 and fermentingorganism collection cone 890, 930 in either of the fermentation tanks870, 910 in the normal, continuous flow operational mode. It will beunderstood that the concepts illustrated and described with respect toFIGS. 20-22 apply equally to the first and second fermenters 870 and910, except where noted.

In the diagram of FIG. 20, the general operation of an “air lift”fermenter design is illustrated. Air is introduced via the outer airspargers 896, 904 adjacent to the bottom ends 876, 916 of the bottominner cylinders 874, 914, and this air naturally rises to the top asillustrated by the arrows sharing a common design with arrow 954. Theaspect ratios of the fermenters 870, 910; i.e., the height to diameterratios of the fermenters 870, 910, are selected to create specifiedpressure differentials between the bottoms 878, 918 and the tops 888,928 of each reactor 870, 910. Typically, at least the first fermenter870 has a high aspect ratio; e.g., 5-6, and an example first fermenterhaving a height of 60 feet and a diameter of 9 feet will create apressure differential of approximately 2 atmospheres or 29.4 pounds persquare inch (2.08 kg per square centimeter) from bottom 878, 918 to top888, 928. As the air rises within the reactors from the bottom innercylinder 874, 914, it expands to multiples of its original volume, andthis upward force and expansion displaces liquid which spills over thetop 880, 920 of the bottom inner cylinder 874, 914 and falls downwardlythrough the space defined between the sidewall of the reactor 872, 912and the sidewall of the bottom inner cylinder 874, 914, as illustratedby the arrows having a common pattern with arrow 952.

The top inner cylinder 884, 924 extends above the liquid level 950, andbecause the top inner cylinder 884, 924 is spaced apart from the bottominner cylinder 874, 914 and the liquid is thereby spilled downwardlyover the top 880, 920 of the bottom inner cylinder 874, 914, little orno net upward velocity is created in the top inner cylinder 884, 924. Asa result, flocculated fermenting organism falls, along with the liquid,downwardly from the top of the bottom inner cylinder 880, 920 toward thebottom 876, 916 of the bottom inner cylinder 874, 914. Also as a resultof little or no net upward velocity in the top inner cylinder 884, 924,a calm area is created in the area or gap between the sidewall of thereactor 872, 912 and the sidewall of the top inner cylinder 884, 924,allowing removal of liquid via liquid outlet conduit 900, 936 that isessentially free of flocculated fermenting organism as illustrated byarrow 956. Air escaping from the liquid above the liquid level 950 isdirected out of the top 888, 928 of the fermenter 870, 910 via the airoutlet conduit 902, 938. Via implementation of the multiple innercylinder design of the fermenters 870, 910, as illustrated in FIGS. 19and 20, air and liquid are separated within the region “A.”

In the bottom inner cylinder 874, 914, the rapid upward flow of the airsupplied to the bottom inner cylinder 874, 914 is balanced with therapid downward fall of liquid in the gap between the reactor 872, 912and the bottom inner cylinder 874, 914. The upward flow of air into thebottom inner cylinder 874, 914 draws the rapidly falling liquid into thebottom 876, 916 of the bottom inner cylinder 874, 916, and circulationof the liquid about the bottom inner cylinder 874, 914, as illustratedby arrows having a common pattern with arrow 952, results in thoroughmixing of the liquid and organisms within the mixing and growth region“B” illustrated in FIG. 19. Additionally, hyperbaric air at the bottom876, 916 of the bottom inner cylinder 874, 914 causes rapid saturationof a high level of oxygen in the liquid. At maximum performance, air israpidly removed; i.e., used, from the downward flow of liquid. The timeof downward liquid travel is low because the net volume of the gapdefined between the sidewall of the reactor 872, 912 and the sidewall ofthe bottom inner cylinder 874, 914 is small, thereby allowing organismsto rapidly reach the high oxygen zone within the bottom inner cylinder874, 914.

FIGS. 21 and 22 illustrate the fermenting organism growth and separationregion “C” illustrated in FIG. 19. FIG. 21 illustrates operation of thefermenter 870, 910 during times when fermenting organism concentrationis being reduced. During such times, the inner air sparger 898, 934 isturned off so that no air flows from the inner air sparger 898, 934 tothe interior of the cone 890, 930, and the outer air sparger 896, 904stays on so that air flows from the outer air sparger 896, 904 about thecone 890, 930 and upwardly through the bottom inner cylinder 874, 914 asillustrated by arrows having a common pattern with arrow 960. Operationof the inner 898, 934 and outer 896, 904 air spargers in this mannerresults in a zone “AA” of low vertical upward velocity directly abovethe cone 890, 930, while normal mixing and aeration of the remainder ofthe fermenter 870, 910, and normal circulation up through the bottominner cylinder 874, 914 and down through the gap between the reactor872, 912 and the bottom inner cylinder 874, 914, is maintained, asillustrated by arrows having a common pattern with arrow 964. The zone“AA” of low vertical upward velocity allows flocculated (and someunflocculated) fermenting organism to settle into the cone 890, 930, asillustrated by arrows having a common pattern with arrow 962. Becausethe lower area of the cone 890, 930 and the fermenting organism exitport “BB” of the cone 890, 930 are substantially remote from turbulence,a high concentration of fermenting organism is allowed to accumulatetherein for subsequent removal.

FIG. 22 illustrates operation of the fermenter 870, 910 during timeswhen fermenting organism concentration is not being reduced. During suchtimes, the inner air sparger 898, 934 is turned on so that air flowsfrom the inner air sparger 898, 934 upwardly from the interior of thecone 890, 930, and the outer air sparger 896, 904 also stays on so thatair flows from the outer air sparger 896, 904 about the cone 890, 930and upwardly through the bottom inner cylinder 874, 914, all asillustrated by arrows having a common pattern with arrow 960. Normalmixing and aeration of the remainder of the fermenter 870, 910, andnormal circulation of liquid up through the bottom inner cylinder 874,914 and down through the gap between the reactor 872, 912 and the bottominner cylinder 874, 914, is maintained, as illustrated by arrows havinga common pattern with arrow 964. Operation of the inner 898, 934 andouter 896, 904 air spargers in this manner results in turbulence andadmixing of flocculated and unflocculated fermenting organism inside ofthe cone 890, 930, precludes settling of fermenting organism in the cone890, 930. Except for fermenting organism that has already entered thefermenting organism exit port “BB” of the cone, as illustrated by thearrow having a common pattern with arrow 962, all fermenting organismadmixed by the operation of the inner air sparger 898, 934 resumescirculation through the fermenter 870, 910 as described hereinabove.

In a typical implementation of the first and second fermenters 870, 910in the fermentation unit 580 illustrated in FIG. 19, the aspect ratio ofthe first fermenter 870 is much greater than that of the secondfermenter 910. For example, the first fermenter 870 may have a height ofapproximately 60 feet and a diameter of approximately 9 feet, resultingin an aspect ratio of approximately 6.67, and the second fermenter 910may have a height of approximately 17 feet and a diameter ofapproximately 12 feet, resulting in an aspect ratio of approximately1.42. The fermenting organism collection cone 890 is therefore typicallysmaller in the first fermenter 870 than in the second fermenter 910.This type of configuration generally allows for high circulationvelocities (low dwell time) and high oxygen-in-solution concentration inthe first fermenter 870, which results in rapid fermentation of thebiomaterial waste stream in the first fermenter 870. Because of thesubstantially lower aspect ratio, the second fermenter 910 hascorrespondingly lower circulation velocity (longer dwell time) and loweroxygen-in-solution concentration.

As described hereinabove, some unflocculated fermenting organism iscollected along with flocculated fermenting organism in the fermentingorganism exit port “BB” of the cone 890 as a result of the operation ofthe first fermenter 870. All of the collected fermenting organism in thefirst fermenter 870 is transferred to the lower portion of the cone 930of the second fermenter 910, and the operation of the second fermenter910, as generally described hereinabove, results in precipitation ofmost, if not all, of the unflocculated fermenting organism provided bythe first fermenter 870, as well as growth and precipitation ofadditional fermenting organism. All such fermenting organism iscollected in the comparatively larger cone 930 of the second fermenter910 for subsequent removal as will be described in greater detailhereinafter.

Further details relating to the biomaterial waste stream fermentationand precipitation processes briefly described hereinabove are disclosedin detail in PCT/US2005/______, entitled FERMENTER AND FERMENTATIONMETHOD (attorney docket no. 35479-77851) and in PCT/US2005/______,entitled FLOCCULATION METHOD AND FLOCCULATED ORGANISM (attorney docketno. 35479-77852), both of which are assigned to the assignee of thepresent invention, and both of which are incorporated herein byreference. Further details relating to some of the structural detailsand to the operation of the inner and outer air spargers 898, 934 and896, 904 respectively are disclosed in detail in PCT/US2005/______,entitled FLUID SPARGER AND DISSIPATER (attorney docket no. 35479-77856),which is assigned to the assignee of the present invention and isincorporated herein by reference.

Referring now to FIGS. 23A-23C, one illustrative embodiment of the firstfermentation tank 870 of FIG. 19 is shown. Referring to FIGS. 23A and23B specifically, both of which show a front elevational view of thefermentation tank 870, the bottom inner cylinder 874 is formed of twoinner cylinders 874A and 874B. The bottom end 876 of the lower bottominner cylinder 874A is supported by a bottom support plate or grid874A′, which is supported by one or more brackets 874A″ mounted to thereactor 872 (see FIG. 23B) above the bottom 878 of the reactor 874. Theupper bottom inner cylinder 874B is mounted to the reactor 872 via oneor more brackets 874B′, and the lower and upper bottom inner cylinders874A and 874B are joined together at adjacent ends via conventionaljoining techniques. The top inner cylinder 884 is positioned within thereactor 872 with the bottom end 882 positioned adjacent to and spacedapart from the top 880 of the upper bottom inner cylinder 874B, and theliquid outlet conduit 900 extends from the side of the reactor 872adjacent to the top inner cylinder 884. The top end 886 of the top innercylinder 884 is positioned adjacent to and spaced apart from the top 888of the reactor 872, and the air outlet conduit 902 extends from the top888 of the reactor 872. The fermenter 870 is supported in its verticalposition by support legs 974, and a clean out/maintenance entrance 972is provided through the reactor 872 and lower bottom inner cylinder 872to allow access to the cone 890 and outer air sparger 896.

The liquid waste inlet conduit 894 extends through the reactor 872 andlower bottom inner cylinder 874A to allow the liquid biomaterial wasteto enter the lower bottom inner cylinder 872 adjacent to the outer airsparger 896. A liquid drain conduit 970 extends upwardly through thebottom end 878 of the reactor 872 to provide for the draining of thefermenter 870 for maintenance or other purposes.

As most clearly shown in FIGS. 23B and 23C, the inner air sparger 898extends through and into the lower end of the cone 890 to supply airinternal to the cone 890 as described hereinabove. An outer air spargerair inlet conduit 980 extends under the bottom 878 of the reactor 872and is split via a T-connection to air supply conduits 982A and 982Beach extending laterally, then parallel via a 90° elbow toward the cone890, then upwardly via another 90° elbow through the bottom 878 andcontinuing through the lower bottom inner cylinder 874A, then laterallyand slightly back from the cone 890 via another 90° elbow. The airsupply conduit 982A is fluidly coupled to a first outer air sparger ring896A via another T-connection, and the air supply conduit 982B isfluidly coupled to a second outer air sparger ring 896B via yet anotherT-connection. The first and second outer air sparger rings 896A and 896Bare each curved structures that generally follow the contour of thereactor 872 between the lower bottom inner cylinder 872 and the cone890. The outer air sparger ring 896A is supported in its elevatedposition relative to the bottom end 876 of the lower bottom innercylinder 874A by support members 984A, 984B and 984C, and the outer airsparger ring 896B is similarly supported in its elevated position bysupport members 984A′, 984B′ and 984C′. The outer air sparger 896 isoperable, as described hereinabove, to supply air to the lower bottominner cylinder 874A.

Referring now to FIGS. 24A-24C, one illustrative embodiment of thesecond fermentation tank 910 of FIG. 19 is shown. Referring to FIG. 24Aspecifically, which shows a front elevational view of the secondfermentation tank 910, the upper end of the bottom inner cylinder 914 ismounted to the sidewall of the reactor 912 by one or more brackets 986A,and the lower end of the bottom inner cylinder 914 is likewise mountedto the sidewall of the reactor 912 by one or more brackets 986B. The topinner cylinder 924 is positioned within the reactor 912 with the bottomend 922 positioned adjacent to and spaced apart from the top end 920 ofthe bottom inner cylinder 914, and the liquid outlet conduit 936 extendsfrom the side of the reactor 912 adjacent to the top inner cylinder 924.The top end 926 of the top inner cylinder 924 is positioned adjacent toand spaced apart from the top 928 of the reactor 912, and the air outletconduit 938 extends from the top 928 of the reactor 912. The upper endof the top inner cylinder 914 is mounted to the sidewall of the reactor912 by one or more brackets 988A, and the lower end of the top innercylinder 914 is likewise mounted to the sidewall of the reactor 912 byone or more brackets 988B. The fermenter 910 is supported in itsvertical position by support legs 985, and a clean out/maintenanceentrance 990 is provided through the reactor 912 and lower bottom innercylinder 912 to allow access to the cone 930 and air spargers 904 and934.

The liquid waste inlet conduit 900 extends through the reactor 912 andbottom inner cylinder 914 to allow the liquid extracted from the firstfermenter 870 to enter the bottom inner cylinder 914 adjacent to the topof the cone 930. A pair of liquid drain conduits 992 extend upwardlythrough the bottom end 918 of the reactor 912 to provide for thedraining of the fermenter 910 for maintenance or other purposes. Theproduct outlet conduit 892 of the first fermenter 870 is fluidly coupledto the lower portion of the cone 930 of the second fermenter 910, andthe product outlet conduit 932 of the second fermenter 910 is alsofluidly connected to a lower portion of the cone 930.

The outer air sparger inlet conduit 902 is fluidly connected to a pairof air conduits 996A and 996B that extend laterally via a T-connection,then upwardly in parallel and toward the cone 930 via a 90° elbow. Theair conduits 996A and 996B continue through the bottom 918 of thereactor 910 and through the bottom 916 of the bottom inner cylinder 914to a position approximately coplanar with the top of the cone 930. Via aT-connection, the air conduits 996A and 996B are in fluid communicationwith the outer air spargers 904A and 904B, respectively. In theillustrated embodiment, as most clearly shown in FIG. 24A, the airconduits 996A and 996B performs the dual functions of supplying inletair to the outer air spargers 904A and 904B and mechanically supportingthe outer air spargers 904A and 904B in their illustrated position. FIG.24B shows a cross-sectional view through the second fermenter 910 thatlooks downwardly on the cone 930, and in FIG. 24B all details relatingto the inner air sparger 934 have been omitted for clarity ofillustration of the outer air sparger 904. In the illustratedembodiment, the outer air sparger 904 includes a first outer air spargerring 904A fluidly coupled to the air conduit 996A, and a second outerair sparger ring 904B fluidly coupled to the air conduit 996B. The firstand second outer air sparger rings 904A and 904B are opposing curvedstructures that generally follow the contour of the reactor 912 betweenthe bottom inner cylinder 914 and the cone 930. The outer air sparger904 is operable, as described hereinabove, to supply air to the bottominner cylinder 914.

Referring again to FIG. 24A, an inner air sparger inlet conduit 994extends laterally into the reactor 912 and bottom inner cylinder 914,and then extends downwardly into fluid communication with the inner airsparger 934 positioned within the cone 930. FIG. 24C shows across-sectional view through the second fermenter 910 that looksdownwardly on the cone 930, and in FIG. 24C all details relating to theouter air sparger 934 have been omitted for clarity of illustration ofthe inner air sparger 934. In the illustrated embodiment, the airconduit 994 extends downwardly into the cone 930 and is fluidlyconnected to a pair of laterally opposing air conduits 998A and 998B bya T-connector. The pair of laterally opposing air conduits 998A and 998Bare parallel to the air conduit 994. The inner air sparger 934 isprovided in the form of a closed ring, and opposite ends of the airconduits 998A and 998B are fluidly connected to the inner air sparger934 by T-connectors. The air inlet conduit 994 supports the inner airsparger 934 in its illustrated position, and the inner air sparger 934is operable, as described hereinabove, to supply air to the interior ofthe cone 930.

Referring now to FIG. 25, a schematic diagram of one illustrativeembodiment of a control system for controlling the fermentation unit 580of FIGS. 12 and 19 is shown. In the illustrated embodiment, the firstfermenter inner air sparger inlet, F1I, is fluidly connected via conduit58 to an inlet of an air control valve 1110 having an outlet fluidlycoupled to the inner air sparger of the first fermenter 870 via theinner air sparger inlet conduit 898 having a check valve and ball valvedisposed in-line therewith. The first fermenter outer air sparger inlet,F1O, is fluidly connected via conduit 60 to an inlet of another aircontrol valve 1112 having an outlet fluidly coupled to the outer airsparger of the first fermenter 870 via the outer air sparger inletconduit 980 having a check valve and ball valve disposed in-linetherewith. The control valve 1110 represents one of the “O” actuators ofthe fermentation unit 580, and is electrically connected to one of theactuator outputs of the PLC circuit 120 via one of the “O” signal paths130 ₁₃. The control valve 1112 represents another one of the “O”actuators of the fermentation unit 580, and is electrically connected toanother one of the actuator outputs of the PLC circuit 120 via anotherone of the “O” signal paths 130 ₁₄. The PLC circuit 120 is configured tocontrol the operation of the air inlet valves 1110 and 1112 by producingappropriate signals on signal paths 130 ₁₃ and 130 ₁₄ respectively. Oneof the “P” sensors included within the fermentation unit 580 is aconventional temperature sensor 122 ₁₄ disposed in fluid communicationwith the interior of the first fermenter 870 and electrically connectedto the PLC circuit 120 via one of the “P” signal paths 124 ₁₄. Thetemperature sensor 122 ₁₄ is operable to produce a temperature signal onsignal path 124 ₁₄ indicative of the temperature of the fluid within thefirst fermenter 870. Another one of the “P” sensors included within thefermentation unit 580 is a conventional pressure sensor 122 ₁₈ disposedin fluid communication with the interior of the first fermenter 870 andelectrically connected to the PLC circuit 120 via one of the “P” signalpaths 124 ₁₈. The pressure sensor 122 ₁₈ is operable to produce apressure signal on signal path 124 ₁₈ indicative of the pressure withinthe first fermenter 870.

The sterilized liquid waste inlet, SLWI, is fluidly connected viaconduit 582 through a first flow reducer, R1, through one side of aconventional heat exchanger HX3, and through a number of ball and checkvalves to the liquid inlet waste inlet conduit 894 of the firstfermenter 870. Another one of the “P” sensors included within thefermentation unit 580 is another conventional temperature sensor 122 ₁₅disposed in fluid communication with the sterilized waste inlet conduit582 between the flow reducer, R1, and the inlet of the heat exchangerHX3, and electrically connected to the PLC circuit 120 via another oneof the “P” signal paths 124 ₁₅. The temperature sensor 122 ₁₅ isoperable to produce a temperature signal on signal path 124 ₁₅indicative of the temperature of sterilized liquid waste entering theheat exchanger HX3. Yet another one of the “P” sensors included withinthe fermentation unit 580 is another conventional temperature sensor 122₁₆ disposed in fluid communication with the sterilized waste inletconduit 582 between the outlet of the heat exchanger HX3 and liquidwaste inlet conduit 894, and electrically connected to the PLC circuit120 via another one of the “P” signal paths 124 ₁₆. The temperaturesensor 122 ₁₆ is operable to produce a temperature signal on signal path124 ₁₆ indicative of the temperature of sterilized liquid waste exitingthe heat exchanger HX3. Still another one of the “P” sensors includedwithin the fermentation unit 580 is a conventional conductivity sensor122 ₁₇ disposed in fluid communication with the sterilized waste inletconduit 582 between the outlet of the heat exchanger HX3 and liquidwaste inlet conduit 894, and electrically connected to the PLC circuit120 via another one of the “P” signal paths 124 ₁₇. The conductivitysensor 122 ₁₇ is operable to produce a conductivity signal on signalpath 124 ₁₇ indicative of the electrical conductivity of sterilizedliquid waste entering the first fermenter 870, and in this regard theconductivity sensor 122 ₁₇ may alternatively be disposed in fluidcommunication with the sterilized liquid waste stream anywhere alongconduit 582 or conduit 894.

The first seed inlet, SD1, is fluidly connected via conduit 46 andthrough a pair of ball valves to the junction of conduits 582 and 894.The seed steam inlet, F12S, is fluidly connected through another ballvalve to the seed inlet conduit 46 between the two ball valves in-linetherewith. Organisms may be added to the first fermenter 870 via the SD1inlet, and this inlet may be cleaned/sterilized via the steam inlet,F12S, via appropriate manual control of the various ball valves.

The coolant flow inlet, CFI, of the fermentation unit 580 is fluidlycoupled via conduit 590 and butterfly valve to an inlet of a coolantfluid pump 1114 having a pump outlet fluidly coupled to a conduit 590′that passes through a number of butterfly and check valves, and throughthe opposite side of the heat exchanger HX3 to the inlet of a flowexpander, R2. The outlet of the flow expander, R2, is fluidly coupled tothe coolant flow outlet, CFO, of the fermentation unit 580 via conduit588. The pump 1114 is electrically connected to a conventional pumpdriver 1116, which also is electrically connected to one of the actuatoroutputs of the PLC circuit 120 via signal path 130 ₁₅. The pump driver1116 represents another one of the “O” actuators, and the PLC circuit120 is configured to control operation of the pump 1114, by producing anappropriate control signal on signal path 130 ₁₅, to thereby control thetemperature of the sterilized liquid waste stream entering the firstfermenter 870 by controlling the flow rate of coolant fluid through theheat exchanger HX3. Another one of the “P” sensors included within thefermentation unit 580 is another conventional temperature sensor 122 ₁₉disposed in fluid communication with conduit 590′ between the outlet ofthe pump 1114 and the coolant fluid inlet of the heat exchanger HX3, andelectrically connected to the PLC circuit 120 via another one of the “P”signal paths 124 ₁₉. The temperature sensor 122 ₁₉ is operable toproduce a temperature signal on signal path 124 ₁₉ indicative of thetemperature of the coolant fluid entering the heat exchanger HX3. Yetanother one of the “P” sensors included within the fermentation unit 580is another conventional temperature sensor 122 ₂₀ disposed in fluidcommunication with the conduit 590′ between the coolant fluid outlet ofthe heat exchanger HX3 and the flow expander, R2, and electricallyconnected to the PLC circuit 120 via another one of the “P” signal paths124 ₂₀. The temperature sensor 122 ₂₀ is operable to produce atemperature signal on signal path 124 ₂₀ indicative of the temperatureof coolant fluid exiting the heat exchanger HX3.

The liquid outlet conduit 900 extending from the liquid outlet of thefirst fermenter 870 is coupled through a control valve 1120, through oneside of another conventional heat exchanger HX4, and through variousball valves to the liquid inlet of the second fermenter 910. The controlvalve 1120 represents another one of the “O” actuators of thefermentation unit 580, and is electrically connected to another one ofthe actuator outputs of the PLC circuit 120 via another one of the “O”signal paths 130 ₁₆. The PLC circuit 120 is configured to control theoperation of the control valve 1120 by producing an appropriate signalon signal path 130 ₁₆. Another one of the “P” sensors included withinthe fermentation unit 580 is a conventional flow sensor or flow meter122 ₂₁ disposed in fluid communication with the liquid outlet conduit900 between the inlet control valve 1120 and the inlet of the heatexchanger HX4, and electrically connected to the PLC circuit 120 via oneof the “P” signal paths 124 ₂₁. The flow sensor or flow meter 122 ₂₁ isoperable to produce a signal on signal path 124 ₂₁ indicative of theflow rate of liquid flowing out of the first fermenter 870 and into thesecond fermenter 910, and as such may be alternatively positionedanywhere along conduit 900. Another one of the “P” sensors includedwithin the fermentation unit 580 is another conventional conductivitysensor 122 ₂₂ disposed in fluid communication with the liquid outletconduit 900 between the flow sensor 122 ₂₂ and the inlet of the heatexchanger HX4, and electrically connected to the PLC circuit 120 via oneof the “P” signal paths 124 ₂₂. The conductivity sensor 122 ₂₁ isoperable to produce a signal on signal path 124 ₂₂ indicative of theelectrical conductivity of the liquid flowing out of the first fermenter870, and as such may be alternatively positioned anywhere along conduit900. Yet another one of the “P” sensors included within the fermentationunit 580 is another conventional temperature sensor 122 ₂₃ disposed influid communication with the liquid outlet conduit 900 between theoutlet of the heat exchanger HX4 and the second fermenter 910, andelectrically connected to the PLC circuit 120 via one of the “P” signalpaths 124 ₂₃. The temperature sensor 122 ₂₃ is operable to produce asignal on signal path 124 ₂₃ indicative of the temperature of the liquidexiting the heat exchanger HX4.

The second seed inlet, SD2, is fluidly connected via conduit 50 andthrough a pair of ball valves to conduit 900. The seed steam inlet,F12S, is fluidly connected through another ball valve to the seed inletconduit 50 between the two ball valves in-line therewith. Organisms maybe added to the second fermenter 910 via the SD2 inlet, and this inletmay be cleaned/sterilized via the steam inlet, F12S, via appropriatemanual control of the various ball valves.

The coolant flow inlet, CFI, of the fermentation unit 580 is alsofluidly coupled via conduit 590 and butterfly valve to an inlet ofanother coolant fluid pump 1132 having a pump outlet fluidly coupled toa conduit 590″ that passes through a number of butterfly and checkvalves, through the opposite side of the heat exchanger HX4, and intofluid communication with the conduit 590′ between the heat exchanger JX3and flow expander, R2, and downstream of the temperature sensor 122 ₁₅.The pump 1132 is electrically connected to another conventional pumpdriver 1134, which also is electrically connected to one of the actuatoroutputs of the PLC circuit 120 via signal path 130 ₁₇. The pump driver1134 represents another one of the “O” actuators, and the PLC circuit120 is configured to control operation of the pump 1132, by producing anappropriate control signal on signal path 130 ₁₇, to thereby control thetemperature of the liquid stream entering the second fermenter 910 bycontrolling the flow rate of coolant fluid through the heat exchangerHX4. Another one of the “P” sensors included within the fermentationunit 580 is another conventional temperature sensor 122 ₂₆ disposed influid communication with conduit 590″ between the outlet of the pump1132 and the coolant fluid inlet of the heat exchanger HX4, andelectrically connected to the PLC circuit 120 via another one of the “P”signal paths 124 ₂₆. The temperature sensor 122 ₂₆ is operable toproduce a temperature signal on signal path 124 ₂₆ indicative of thetemperature of the coolant fluid entering the heat exchanger HX4. Yetanother one of the “P” sensors included within the fermentation unit 580is another conventional temperature sensor 122 ₂₇ disposed in fluidcommunication with the conduit 590″ between the coolant fluid outlet ofthe heat exchanger HX4 and conduit 590′, and electrically connected tothe PLC circuit 120 via another one of the “P” signal paths 124 ₂₇. Thetemperature sensor 122 ₂₇ is operable to produce a temperature signal onsignal path 124 ₂₇ indicative of the temperature of coolant fluidexiting the heat exchanger HX4.

The air outlet conduit 902 extending from the air outlet of the firstfermenter 870 is coupled through a ball valve to the outer air spargerinlet of the second fermenter 910. Another one of the “P” sensorsincluded within the fermentation unit 580 is another conventionalpressure sensor 122 ₂₄ disposed in fluid communication with conduit 902and electrically connected to the PLC circuit 120 via another one of the“P” signal paths 124 ₂₄. The pressure sensor 122 ₂₄ is operable toproduce a pressure signal on signal path 124 ₂₄ indicative of thepressure of gas exiting the first fermenter 870 and entering the outerair sparger inlet of the second fermenter 910. Yet another one of the“P” sensors included within the fermentation unit 580 is a conventionalmass flow sensor or mass flow meter 122 ₂₅ disposed in-line with conduitand electrically connected to the PLC circuit 120 via another one of the“P” signal paths 124 ₂₅. The mass flow sensor or mass flow meter 122 ₂₅is operable to produce a signal on signal path 124 ₂₅ indicative of themass flow rate of gas exiting the first fermenter 870 and entering theout air sparger inlet of the second fermenter 910. A pressure reliefvalve 1122 is also disposed in fluid communication with conduit 902. Thepressure relief valve 1122 is a mechanical valve having an openingpressure that is set to prevent over-pressure and/or vacuum conditionswithin conduit 902.

The second fermenter inner air sparger inlet, F2I, is fluidly connectedvia conduit 62 to an inlet of an air control valve 1128 having an outletfluidly coupled via a check valve and ball valve to the inner airsparger inlet conduit 994 of the second fermenter 910. The control valve1128 represents another one of the “O” actuators of the fermentationunit 580, and is electrically connected to one of the actuator outputsof the PLC circuit 120 via one of the “O” signal paths 130 ₁₈. The PLCcircuit 120 is configured to control the operation of the air inletvalve 1128 by producing an appropriate signal on signal path 130 ₁₈. Thesecond fermenter inner air sparger inlet, F2I, is also coupled viaconduit 62 to an inlet of another air control valve 1126 having anoutlet fluidly coupled via a check valve and a ball valve to the airoutlet conduit 902. The control valve 1126 represents yet another one ofthe “O” actuators of the fermentation unit 580, and is electricallyconnected to another one of the actuator outputs of the PLC circuit 120via another one of the “O” signal paths 130 ₁₉. The PLC circuit 120 isconfigured to control the operation of the air inlet valve 1126 byproducing an appropriate signal on signal path 130 ₁₉ to selectivelysupplement air provided to the outer air sparger of the second fermenter910. Another one of the “P” sensors included within the fermentationunit 580 is a conventional pressure sensor 122 ₂₈ disposed in fluidcommunication with the interior of the second fermenter 910 andelectrically connected to the PLC circuit 120 via another one of the “P”signal paths 124 ₂₈. The pressure sensor 122 ₂₈ is operable to produce apressure signal on signal path 124 ₂₈ indicative of the pressure withinthe second fermenter 870. Another one of the “P” sensors included withinthe fermentation unit 580 is another conventional temperature sensor 122₂₉ disposed in fluid communication with the interior of the secondfermenter 910 and electrically connected to the PLC circuit 120 via oneof the “P” signal paths 124 ₂₉. The temperature sensor 122 ₂₉ isoperable to produce a temperature signal on signal path 124 ₂₉indicative of the temperature of the fluid within the second fermenter910.

The product outlet conduit 892 fluidly connected to the outlet of thecone 890 of the first fermenter 870 is fluidly connected through a ballvalve to an inlet of a product outlet pump 1148 having a pump outletfluidly coupled to an inlet of a control valve 1152. An outlet of thecontrol valve 1152 is fluidly coupled through another ball valve to theproduct inlet of the second fermenter 910 via conduit 1154. The pump1148 is electrically connected to a conventional pump driver 1150 thatis also electrically connected to an actuator output of the PLC circuit120 via signal path 130 ₂₂. In some embodiments, the pump driver 1150may also be electrically connected to a sensor input of the PLC circuit120 via signal path 124 ₃₃ as shown in phantom in FIG. 25. The PLCcircuit 120 is configured to control the speed of the pump 1148 in aknown manner by producing an appropriate actuator control signal onsignal path 130 ₂₂. The pump driver 1150 is responsive to the actuatorcontrol signal supplied by the PLC 120 on signal path 130 ₂₂ to drivethe pump 1148. In the illustrated embodiment, the pump driver 1150and/or pump 1148 further includes a “sensor” for determining andmonitoring the operating torque of the pump 1148. Such a “sensor” may bea conventional strain-gauge type torque sensor operatively coupled to arotating drive shaft of the pump 1148 and operable to produce a sensorsignal corresponding to the operating torque of the pump 1148, or mayalternatively be a so-called virtual sensor implemented in the form ofone or more software algorithms resident within the PLC circuit 120 andresponsive to one or more measurable operating parameters associatedwith the pump driver 1150 and/or pump 1148 to derive or infer theoperating torque value. For example, the pump driver 1150 may include acurrent sensor producing a current sensor signal indicative of drivecurrent being drawn by the pump driver 1148, and/or the pump 1150 mayinclude a position and/or speed sensor producing a signal correspondingto the rotational speed and/or position of the pump 1148. The PLCcircuit 120 may be responsive to any such sensor signals, and/or toother information relating to the operation of the pump driver 1150and/or pump 1148, to estimate the operating torque of the pump 1148 as aknown function thereof. In any case, the signal path 124 ₃₃ carries oneor more torque feedback signals to the PLC circuit 120 from which theoperating torque of the pump 1148 may be determined directly orestimated. The control valve 1152 is likewise electrically connected toanother one of the actuator outputs of the PLC circuit 120 via signalpath 130 ₂₃. The pump driver 1150 and control valve 1152 representadditional ones of the “O” actuators, and the PLC circuit 120 isconfigured to control operation of the pump 1150 and the control valve1152, by producing appropriate control signals on signal paths 130 ₂₂and 130 ₂₃ respectively, to control the timing and flow of fermentingorganism from the first fermenter 870 to the second fermenter 910.

The drain outlet 970 of the first fermenter 780 is fluidly coupledthrough a ball valve to one end of a conduit 1130 having an opposite endfluidly coupled to a liquid outlet conduit 1142. The drain outlet 992 ofthe second fermenter 910 is fluidly coupled through another ball valveto the junction of conduits 1130 and 1142. The liquid outlet conduit1142 is fluidly coupled through a pair of ball valves to an inlet of aliquid outlet pump 1144 having a pump outlet fluidly coupled through aball valve to the residual liquid outlet, RLO, of the fermentation unit580 and to the residual liquid outlet conduit 74. The waste returninlet, WRI, of the fermentation unit 580 that is fluidly coupled toconduit 596 is also fluidly coupled through a check valve to theresidual liquid outlet, RLO. The liquid outlet conduit 936 that isfluidly coupled to the liquid outlet of the second fermenter 910 iscoupled through a liquid outlet control valve 1140 and check valve tothe liquid outlet conduit 1142. The liquid outlet pump 1144 iselectrically connected to another conventional pump driver 1146, whichalso is electrically connected to another one of the actuator outputs ofthe PLC circuit 120 via signal path 130 ₂₁. The control valve 1140 islikewise electrically connected to another one of the actuator outputsof the PLC circuit 120 via signal path 130 ₂₀. The pump driver 1146 andcontrol valve 1140 represent additional ones of the “O” actuators, andthe PLC circuit 120 is configured to control operation of the pump 1144and the control valve 1140, by producing appropriate control signals onsignal paths 130 ₂₁ and 130 ₂₀ respectively, to control the timing andflow of liquid out of the second fermenter 910. Additionally, andindependently of control valve 1140, the liquid outlet pump 1144 may becontrolled by the PLC circuit 120 to drain liquid from the first and/orsecond fermenter 870, 910, via drain outlets 970 and 992 respectively,at a desired flow rate.

Another one of the “P” sensors included within the fermentation unit 580is a conventional flow sensor or flow meter 122 ₃₁ disposed in fluidcommunication with the liquid outlet conduit 932 upstream of the controlvalve 1140, and electrically connected to the PLC circuit 120 viaanother one of the “P” signal paths 124 ₂₁. The flow sensor or flowmeter 122 ₃₁ is operable to produce a signal on signal path 124 ₃₁indicative of the flow rate of liquid flowing out of the secondfermenter 910 via the liquid outlet conduit 936, and as such may bealternatively positioned anywhere along conduit 936. Yet another one ofthe “P” sensors included within the fermentation unit 580 is anotherconventional conductivity sensor 122 ₃₂ disposed in fluid communicationwith the liquid outlet conduit 936 upstream of the flow sensor or flowmeter 122 ₃₁ and electrically connected to the PLC circuit 120 viaanother one of the “P” signal paths 124 ₃₂. The conductivity sensor 122₃₂ is operable to produce a signal on signal path 124 ₃₂ indicative ofthe conductivity of the liquid flowing out of the second fermenter 910via conduit 936, and as such may be alternatively positioned anywherealong conduit 936.

The air outlet conduit 938 extending from the air outlet of the secondfermenter 910 is coupled through a mechanical control valve 1136 to aninlet of a conventional water separation unit 1138. A water drain outletof the water separation unit 1138 is fluidly coupled to the liquidoutlet conduit 1142, and the air outlet of the water separation unit isfluidly coupled to the gas outlet, GO, of the fermentation unit 580 andalso fluidly coupled to conduit 68. Optionally, a control valve (notshown) may be interposed between the water drain outlet of the waterseparation unit 1138 and the liquid outlet conduit 1142, which would beelectrically controlled by the PLC circuit 120. In this embodiment, thewater separation unit 1142 may thus be drained under the control of thePLC circuit 120. The control valve 1136 is a mechanical pressure controlvalve having a manually selectable set pressure value. The control valve1136 is operable in a known manner to maintain the set air pressurewithin conduit 938. The water separation unit is operable in a knownmanner to condense water from the gas exiting the second fermenter 910via conduit 938, and to direct the condensed water to the liquid outletconduit 1142 while directing the remaining gas to the gas outlet, GO, ofthe fermentation unit 580. Another one of the “P” sensors includedwithin the fermentation unit 580 is another conventional mass flowsensor or mass flow meter 122 ₃₀ disposed in fluid communication withthe gas outlet, GO, and electrically connected to the PLC circuit 120via another one of the “P” signal paths 124 ₃₀. The mass flow sensor ormass flow meter 122 ₃₀ is operable to produce a signal on signal path124 ₃₀ indicative of the mass flow rate of gas exiting the secondfermenter 910, and as such may be alternatively positioned anywherealong the air outlet conduit 936.

The product outlet conduit 932 fluidly coupled at one end to the outletof the cone 930 of the second fermenter 910 is fluidly coupled at itsopposite end through a control valve 1156 and a ball valve to the inletof a product outlet pump 1158 having a pump outlet fluidly coupled tothe product outlet, POF, of the fermentation unit 580 and also to theconduit 598. The pump 1158 is electrically connected to anotherconventional pump driver 1160 that is also electrically connected to anactuator output of the PLC circuit 120 via signal path 130 ₂₅. In someembodiments, the pump driver 1160 may also be electrically connected toa sensor input of the PLC circuit 120 via signal path 124 ₃₂ as shown inphantom in FIG. 25. The PLC circuit 120 is configured to control thespeed of the pump 1158 in a known manner by producing an appropriateactuator control signal on signal path 130 ₂₅. The pump driver 1160 isresponsive to the actuator control signal supplied by the PLC 120 onsignal path 130 ₂₅ to drive the pump 1158. In the illustratedembodiment, the pump driver 1160 and/or pump 1158 further includes a“sensor” for determining and monitoring the operating torque of the pump1158, wherein such a “sensor” may be as described hereinabove withrespect to the description of the pump driver 1150. The PLC circuit 120may be responsive to any such sensor signals, and/or to otherinformation relating to the operation of the pump driver 1160 and/orpump 1158, to estimate the operating torque of the pump 1158 as a knownfunction thereof. In any case, the signal path 124 ₃₂ carries one ormore torque feedback signals to the PLC circuit 120 from which theoperating torque of the pump 1158 may be determined directly orestimated. The control valve 1156 is likewise electrically connected toanother one of the actuator outputs of the PLC circuit 120 via signalpath 130 ₂₄. The pump driver 1160 and control valve 1156 representadditional ones of the “O” actuators, and the PLC circuit 120 isconfigured to control operation of the pump 1158 and the control valve1156, by producing appropriate control signals on signal paths 130 ₂₅and 130 ₂₄ respectively, to control the timing and flow of fermentingorganism from the second fermenter 870 to the pasteurization unit 595.

The fermentation unit 580 just described includes a number of manuallyactuated butterfly valves, ball valves and check valves as illustratedin FIG. 17. The ball valves and butterfly valves are included within thefermentation unit 580 at various locations to allow for bypassing of,and maintenance or replacement of, various components of thefermentation unit 580, and some are also used in relation to pre-startsterilization, cleaning and seeding operations. The check valves, on theother hand, are provided at various locations within the fermentationunit to ensure unidirectional flow therethrough of gas and/or liquid.

Referring now to FIGS. 26A-26H, a flowchart of one illustrativeembodiment of a software control algorithm 1180 for controlling afermentation unit of the type illustrated in FIGS. 12 and 19-24C via thecontrol system of FIG. 25. It will be understood that the softwarecontrol algorithm 1180 represents one illustrative strategy forcontrolling the fermentation unit 580 during normal, continuous flowoperation of the biomaterial waste processing system 10, and that thefermentation unit 580 may be controlled differently during otheroperational modes of the biomaterial waste processing system 10. Thesoftware algorithm 1180 includes a number of different and independentlyexecuting control routines, and each of these different control routineswill be described separately. For example, as illustrated in FIG. 26A,the control algorithm 1180 includes a first control routine 1182 forcontrolling the liquid level within the first fermenter 870. The controlroutine 1182 begins at step 1184 where the PLC circuit 120 is operableto determine the operating pressure, P1, of the first fermenter 870 bymonitoring the pressure signal produced by the pressure sensor 122 ₁₈ onsignal path 124 ₁₈. Thereafter at step 1186, the PLC circuit 120 isoperable to determine the pressure, P2, of gas exiting the firstfermenter 870 by monitoring the pressure signal produced by the pressuresensor 122 ₂₄ on signal path 124 ₂₄. Following step 1186, the PLCcircuit 120 is operable at step 1188 to compare the difference betweenP1 and P2 to a design pressure, P_(DES1), where P_(DES1) corresponds toa pressure equivalent of the desired liquid level within the firstfermenter 870.

If, at step 1188, the PLC circuit 120 determines that (P1−P2) is greaterthan P_(DES1), indicating that the liquid level within the firstfermenter 870 is higher than desired, the PLC circuit 120 is operablethereafter at step 1190 to increase the opening of the liquid outletvalve 1120, by producing an appropriate actuator control signal onsignal path 130 ₁₆, to increase the flow of liquid exiting the firstfermenter 870. If, on the other hand, the PLC circuit 120 determines atstep 1188 that (P1−P2) is not greater than P_(DES1), execution of thecontrol routine 1182 advances to step 1192 where the PLC circuit isagain operable to compare the difference between P1 and P2 to the designpressure, P_(DES1). If, at step 1192, the PLC circuit determines that(P1−P2) is less than P_(DES1), indicating that the liquid level withinthe first fermenter 870 is lower than desired, the PLC circuit 120 isoperable thereafter at step 1194 to decrease the opening of the liquidoutlet valve 1120, by producing an appropriate actuator control signalon signal path 130 ₁₆, to decrease the flow of liquid exiting the firstfermenter 870. If, on the other hand, the PLC circuit 120 determines atstep 1192 that (P1−P2) is not less than P_(DES1), execution of thecontrol routine 1182 loops back to step 1184 as it also does followingexecution of steps 1190 and 1194.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1200, as illustrated in FIG. 26B, for controlling theoperating temperature of the first fermenter 870 by controlling thetemperature of the sterilized liquid waste entering the first fermenter870 via control of coolant fluid flow through the heat exchanger HX3.The control routine 1200 begins at step 1202 where the PLC circuit 120is operable to determine the flow rate of coolant fluid, CF3, from thecooling tower unit 586 to the heat exchanger HX3. In the illustratedembodiment, the PLC 120 is operable to execute step 1202 by computingCF3 as a function of the flow rate of the biomaterial waste entering thefermentation unit 580 via the sterilized liquid waste inlet conduit 582,the temperature difference between the biomaterial waste entering andexiting HX3 and the temperature difference between the cooling fluidentering and exiting HX3. In particular, the PLC 120 is operable at step1202 to compute CF3 according to the equation CF3=F122 ₃*(T122 ₁₅−T122₁₆)/(T122 ₁₉−T122 ₂₀), where F122 ₃ is the biomaterial waste flow ratesignal produced by the flow sensor 122 ₃ comprising part of thesterilization unit 570 as illustrated in FIG. 13A, T122 ₁₅ is thetemperature signal produced by the temperature sensor 122 ₁₅ on signalpath 124 ₁₅ and represents the temperature of the biomaterial wasteentering HX3, T122 ₁₆ is the temperature signal produced by thetemperature sensor 122 ₁₆ on signal path 124 ₁₆ and represents thetemperature of the biomaterial waste exiting HX3, T122 ₁₉ is thetemperature signal produced by the temperature sensor 122 ₁₉ on signalpath 124 ₁₉ and represents the temperature of the cooling fluid enteringHX3 from the cooling tower unit 586, and T122 ₂₀ is the temperaturesignal produced by the temperature sensor 122 ₂₀ on signal path 124 ₂₀and represents the temperature of the cooling fluid exiting HX3.Alternatively, the coolant flow path through HX3 may include a flowmeter or sensor, and in this embodiment the PLC 120 may be operable toexecute step 1202 by monitoring the flow signal produced by such a flowmeter or sensor. In any case, the execution of routine 1200 advancesfrom step 1202 to step 1204 where the PLC circuit 120 is operable todetermine the operating temperature, T1, of the first fermenter 870 bymonitoring the temperature signal produced by the temperature sensor 122₁₄ on signal path 124 ₁₄. Thereafter at step 1206, the PLC circuit 120is operable to compare the temperature, T1, of the first fermenter 870to a design temperature, T_(D1), wherein T_(D1) corresponds to a desiredoperating or fermenting temperature of the first fermenter 870.

If, at step 1206, the PLC circuit 120 determines that T1 is greater thanT_(D1), indicating that the operating temperature of the first fermenter870 is greater than the design temperature, T_(D1), execution of thecontrol routine 1200 advances to step 1208 where the PLC circuit 120 isoperable to compare the cooling fluid flow rate, CF3, through HX3 to amaximum flow rate value, MAXF3, wherein MAXF3 corresponds to a desiredmaximum flow rate of cooling fluid from the cooling tower unit 586. If,at step 1208, the PLC circuit 120 determines that CF3 is greater than orequal to MAXF3, routine execution advances to step 1210 where the PLCcircuit 120 is operable to decrease the flow of biomaterial waste to thefermentation unit 580. In one embodiment, the PLC circuit 120 isoperable to execute step 1210 by decreasing the speed of the biomaterialwaste pump 612 forming part of the sterilization unit 570 as illustratedin FIG. 13A. Alternatively or additionally, the PLC circuit 120 may beoperable to execute step 1210 by controlling the diverter valve 638 ofthe sterilization unit 570 to divert at least some of the biomaterialwaste stream exiting the sterilization loop 630 back through thesterilization unit 570 to thereby decrease the flow rate of biomaterialwaste exiting the sterilization unit 570. Alternatively or additionallystill, the PLC circuit 120 may be operable to execute step 1210 bycontrolling the biomaterial waste return valve 622 to return at leastsome of the biomaterial waste stream flowing through the sterilizationunit 570 back to the biomaterial waste source 20 (FIG. 1) to therebydecrease the flow rate of biomaterial waste exiting the sterilizationunit 570. In any case, execution of the routine 1200 loops from step1210 back to step 1202.

If, at step 1208, the PLC circuit 120 determines that the CF3 is lessthan MAXF3, routine execution advances to step 1212 where the PLCcircuit 120 is operable to compare the speed of the pump 1114 (P3)supplying the cooling fluid from the cooling tower unit 586 to HX3 to amaximum pump speed, MAXSP3, wherein MAXSP3 corresponds to a maximum pumpspeed value that may be arbitrary or may be dictated by the physicalproperties of the pump 1114. In either case, if the PLC circuit 120determines at step 1212 that the speed of the pump P3 is greater than orequal to MAXSP3, routine execution advances to step 1214 where the PLCcircuit 120 is operable to stop the flow of biomaterial waste to thefermentation unit 580. In one embodiment, the PLC circuit 120 isoperable to execute step 1214 by deactivating the biomaterial waste pump612 forming part of the sterilization unit 570 as illustrated in FIG.13A. Alternatively or additionally, the PLC circuit 120 may be operableto execute step 1214 by controlling the diverter valve 638 of thesterilization unit 570 to divert the biomaterial waste stream exitingthe sterilization loop 630 back through the sterilization unit 570 tothereby stop the flow rate of biomaterial waste exiting thesterilization unit 570. Alternatively or additionally still, the PLCcircuit 120 may be operable to execute step 1210 by controlling thebiomaterial waste return valve 622 to return the biomaterial wastestream flowing through the sterilization unit 570 back to thebiomaterial waste source 20 (FIG. 1) to thereby stop the flow rate ofbiomaterial waste exiting the sterilization unit 570. In any case,execution of the routine 1200 advances from step 1214 to step 1218 wherethe PLC circuit 120 is operable to pause until the temperature, T1, ofthe fermenter 870 is less than or equal to the design temperature, TD1.Thereafter, routine execution advances to step 1220 where the controlcircuit is operable to control the flow of the biomaterial waste streamentering the fermentation unit 580, using any of the techniques justdescribed, to resume the flow of biomaterial waste into the fermentationunit 580. Thereafter, execution of the routine 1200 loops back to step1202. If, at step 1212, the PLC circuit 120 determines that the speed ofthe cooling fluid pump P3 is less than MAXSP3, routine executionadvances to step 1216 where the PLC circuit 120 is operable to increasethe speed of the pump P3 by appropriately controlling the pump driver1116. Thereafter, routine execution loops back to step 1202.

If, at step 1206, the PLC circuit 120 determines that the temperature,T1, of the fermenter 870 is greater than the design temperature, TD1,routine execution advances to step 1222 where the PLC circuit 120 isoperable to determine whether T1 is less than TD1. If not, then T1=TD1and routine execution advances to step 1224 where the PLC circuit 120 isoperable to maintain the current speed of the pump P3 by appropriatelycontrolling the pump driver 1116. If, at step 1222, the PLC circuit 120determines that T1 is less than TD1, routine execution advances to step1226 where the PLC circuit 120 is operable to decrease the speed of thepump P3 by appropriately controlling the pump driver 1116. Routineexecution loops from either of steps 1224 and 1226 back to step 1202.

The PLC circuit 120 is operable, under the direction of the routine1200, to control the temperature, T1, of the first fermenter 870 bycomparing T1 to a design temperature, TD1, and increasing the speed ofthe pump 1114 (P3) supplying cooling fluid from the cooling tower unit586 to the heat exchanger HX3 if T1 is greater than TD1, the flow rateof the cooling fluid through HX3 is less than a maximum cooling fluidflow rate, MAXF3, and the speed of the pump 1114 is not greater than orequal to a maximum pump speed, MAXSP3. If, however, T1 is greater thanTD1 and the flow rate of the cooling fluid through HX3 is greater thanor equal to MAXF3, then T1 cannot be lowered by increasing the speed ofthe pump 1114, and the flow rate of the biomaterial waste into thefermentation unit 580 is instead decreased. If T1 is greater than TD1and the flow rate of the cooling fluid through HX3 is less than MAXF3but the speed of the pump 1114 is greater than or equal to the maximumpump speed, MAXSP3, then no action of the cooling fluid pump 1114 willresult in further cooling of the biomaterial waste stream, and in thiscase the flow of biomaterial waste into the fermentation unit 580 isstopped until T1 becomes less than or equal to TD1. If T1 is less thanTD1, the speed of the pump 1114 is decreased, and if T1 is equal to TD1the speed of the pump 1114 is maintained at its current pump speed.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1228, as illustrated in FIG. 26C, for controllingcollection of the fermenting organism, e.g., yeast or other fermentingorganism, within the lower portion of the cone 890 of the firstfermenter 870 as illustrated in FIGS. 19 and 21-23C. It will beunderstood that the control routine 1228 represents one embodiment of acontrol routine for controlling fermenting organism collection withinthe fermenter 870 during normal, continuous flow operation, and that airflow into the outer and inner air spargers 896 and 898 respectively ofthe fermenter 870 will typically be established and controlled prior tonormal, continuous flow operation by the PLC circuit 120. Prior tofermentation, e.g., prior to the normal, continuous flow operation ofthe first fermenter 870, the PLC circuit 120 is operable to determine abaseline exit gas mass flow rate as a known function of measured exitgas mass flow rate, e.g., from the mass flow rate signal produced by themass flow sensor or meter 1225, ambient air temperature, e.g., from theambient air temperature signal produced by the ambient temperaturesensor 122 ₁₂ associated with the cooling tower unit 586 (see FIG. 17),and relative humidity, e.g., from the relative humidity signal producedby the relative humidity sensor 122 ₁₃ forming part of the cooling towerunit 586, wherein the ambient temperature and relative humidityinformation are used to estimate or otherwise calculate a dew pointvalue using known relationships therebetween. The control routine 1228begins at step 1230 where the PLC circuit 120 is operable to determinethe exit gas mass flow rate, e.g., mass flow rate of air exiting thefermenter 870, during the normal, continuous flow operating mode, e.g.,during fermentation, by monitoring the mass flow signal produced by themass flow meter or sensor 122 ₂₅ illustrated in FIG. 25. Thereafter atstep 1232, the PLC circuit 120 is operable to control the inner spargerinlet valve 1110 and outer sparger inlet valve 1112 respectively of thefermenter 870 to drive the flow rate of air exiting the fermenter 870 toa design air flow exit value, F1AED, wherein F1AED represents a targetair flow value that will depend, at least in part, on the physicaldimensions of the fermenter 870, the flow rate of the biomaterial wastethrough the fermentation unit 580, the type of biomaterial waste andother factors.

Following step 1232, the PLC circuit 120 is operable at step 1234 tomonitor one or more excess fermentation organism indicators, F1E.Following step 1234, the PLC circuit 120 is operable at step 1236 todetermine whether the one or more excess fermentation organismindicators, F1E, indicate an excess of the fermentation organism withinthe fermenter 870. If not, the routine 1228 continually loops back tostep 1234 until F1E indicates a fermentation organism excess. When thePLC circuit 120 determines at step 1236 that F1E indicates afermentation organism excess, execution of the routine 1228 advances tostep 1238. Details relating to some example strategies for determiningwhen a fermentation organism excess condition exists according to steps1234 and 1236 will be described hereinafter following the description ofthe general steps of the routine 1228.

At step 1238, the PLC circuit 120 is operable to reset a fermentationorganism collection timer. Thereafter at step 1240, the PLC circuit 120is operable to control the inner sparger inlet valve 1110 to a closedposition to stop the flow of air to the inner sparger 898 of thefermenter 870. Thereafter at step 1242, the PLC circuit 120 is operableto determine the mass flow rate, F1AE, of gas exiting the fermenter 870by monitoring the mass flow rate signal produced by the mass flow meteror sensor 122 ₂₅, and at the following step 1244 the PLC circuit 120 isoperable to control the outer sparger inlet valve 1112 to increase theair flow to the outer sparger 896 to compensate for turning off the flowof air to the inner sparger 898 at step 1240. In the illustrativeembodiment of routine 1228, it is desirable to maintain constant massair flow through the fermenter 870, and the PLC circuit 120 isaccordingly operable at step 1244 to control the outer sparger inletvalve 1112 to increase the air flow to the outer sparger 896 to an airflow level that maintains the mass air flow exiting the fermenter 870 ata constant level. Following step 1244, the PLC circuit 120 is operableat step 1246 to continually loop back to step 1246 until the F1collection timer has timed out. Thereafter at step 1248, the PLC circuitis operable to return the positions of the outer and inner air spargers896 and 898 respectively of the fermenter 870 to their pre-collectionvalve positions. Execution of the routine loops from step 1248 back tostep 1230.

By stopping the flow of air to the inner sparger 898 of the fermenter870 at step 1240 the fermenting organism present in and above the cone890 settles, and is collected within, the lower portion of the cone 890,thereby reducing the total amount of the fermentation organism beingcirculated through the fermenter 870. In the illustrated embodiment,airflow to the inner sparger 898 of the fermenter 870 is turned off fora time period defined by the timeout duration of the F1 collectiontimer. The timeout duration of the F1 collection timer may beestablished according to any one or more of a number of timerstrategies. For example, the timeout period of the F1 collection timermay be set to a constant value based on the physical dimensions of thefermenter 870, composition and flow rate of the biomaterial waste, typeof fermenting organism and/or other factors. As another example, thetimeout period of the F1 collection timer may be set as a function ofthe amount of time that has elapsed since the fermenting organism waslast collected. As yet another example, the timeout period of the F1collection timer may be set as a function of the change in conductivityof the biomaterial waste across the fermenter 870. In this embodiment,the routine 1228 will include a number of steps between steps 1244 and1246 wherein the PLC circuit 120 is operable to determine theconductivity of the biomaterial waste entering the fermenter 870 bymonitoring the output of the conductivity sensor 122 ₁₇, to determinethe conductivity of the biomaterial waste exiting the fermenter 870 bymonitoring the output of the conductivity sensor 122 ₂₂, and todetermine the timeout period of the F1 collection timer, correspondingto the time that the inner sparger 898 is turned off, as a function ofthe corresponding input and output conductivity values. Those skilled inthe art will recognize other strategies for determining an appropriatetime out period of the F1 collection timer, and any such otherstrategies are intended to fall within the scope of the claims appendedhereto. In any case, the fermenting organism is collected within thelower portion of the cone 890 such that when air flow to the innersparger 898 is thereafter restored, the fermenting organism collectedwithin the lower portion of the cone 890 remains in the lower portion ofthe cone 890 for subsequent extraction.

The PLC circuit 120 is generally operable to execute steps 1234 and 1236to determine whether an excess amount of the fermenting organism existsin the fermenter 870 by monitoring and processing one or more operatingparameters of the fermenter 870. Particular ones or combinations of theoperating parameters of the fermenter 870 used to determine whether anexcess of the fermenting organism exists in the fermenter 870 willdepend on a number of factors including, but not limited to, thephysical dimensions of the fermenter 870, the composition and flow rateof the biomaterial waste, the type of fermenting organism, and the like.As one illustrative example, the following list represents one or moreparameters that may be monitored to determine whether an excess amountof the fermenting organism exists in the fermenter 870 in the case wherethe fermenter 870 has the physical dimensions given by example inreference to FIGS. 23A-23C, where the biomaterial waste is cattle wastehaving variable nutrient content, and where the flow rate of the cattlewaste through the fermenter 870 is approximately 100 gallons (379liters) per minute:

1. mass flow rate of gas (air) exiting the fermenter 870,

2. derivative of 1,

3. change, e.g., decrease, in conductivity across the fermenter 870,

4. derivative of 2,

5. BTU generated in the fermenter 870, and

6. ratios of one or more combinations of 1-5.

Those skilled in the art will recognize that the foregoing list may omitone or more items and/or include other operating parameters notspecifically listed, and that any such alternate list will typically bedictated by the specific application of the biomaterial waste processingsystem 10.

In the illustrated example, the fermentation of cattle waste willgenerally replace oxygen with carbon dioxide, and the fermenter 870 issized to allow no more fermentation than the amount of incoming air willsupport. Thus, if the mass flow rate of gas exiting the fermenter 870increases beyond a predetermined ratio of the exit gas mass flow rateand the baseline exit gas mass flow rate determined prior tofermentation, or beyond a predetermined derivative of the baseline exitgas mass flow rate, this is an indication that the fermenter 870 doesnot have sufficient incoming airflow to support the amount offermentation occurring in the fermenter 870. Subsequent reduction andcollection of some of the fermenting organism circulating through thefermenter 870 will reduce the total amount of fermentation, therebydecreasing the mass flow rate of gas exiting the fermenter 870. In thisexample, the PLC circuit 120 may be operable at steps 1232 and 1234 todetermine whether an excess of the fermentation organism exists in thefermenter 870 by monitoring the flow rate of gas (air) exiting thefermenter 870 and advancing to step 1238 if this exit gas mass flow rateincreases above the aforementioned ratio or derivative value. The PLCcircuit 120 may be operable to supplement the exit gas mass flow rateinformation with the derivative of the exit gas mass flow rate for morea more precise determination of an excess fermentation organismcondition. In any case, the PLC circuit 120 is operable to maintain anarray of such exit gas mass flow rate data, and to perform conventionalregression analyses to track and predict behavior of this data. In theillustrated example, the exit gas mass flow rate data is a highlysensitive indicator of excess fermenting organism in the fermenter 870.

The heat (BTU) generated by the metabolic activity within the fermenter870 is given by the equation BTU=F122 ₃*(TD1−T122 ₁₆), where F122 ₃ isthe biomaterial waste flow rate signal produced by the flow sensor 122 ₃comprising part of the sterilization unit 570 as illustrated in FIG.13A, TD1 is the design fermentation temperature of the fermenter 870,and T122 ₁₆ is the temperature signal produced by the temperature sensor122 ₁₆ on signal path 124 ₁₆ and represents the temperature of thebiomaterial waste exiting HX3 and entering the fermenter 870. BTU isalso the sum of the catabolic activity and the anabolic activity withinthe fermenter 870, where the difference in the conductivity across thefermenter 870 is a direct measure of the anabolic activity, e.g.,anabolic activity=K*(C122 ₁₇−C122 ₂₂), where K is a constant, C122 ₁₇ isthe conductivity signal produced by the conductivity sensor 122 ₁₇ andrepresents the conductivity of the biomaterial waste entering thefermenter 870, and C122 ₂₂ is the conductivity signal produced by theconductivity sensor 122 ₂₂ and represents the conductivity of thebiomaterial waste exiting the fermenter 870. The catabolic activity,CA1, within the fermenter 870 is then the difference between the BTUvalue and the anabolic activity according to the equation CA1=F122₃*(TD1−T122 ₁₆)−K*(C122 ₁₇−C122 ₂₂). In this example, the PLC circuit120 may be alternatively or additionally operable at steps 1232 and 1234to determine whether an excess of the fermentation organism exists inthe fermenter 870 by computing the catabolic activity, CA1, according tothe above equation and advancing to step 1238 if CA1 falls below athreshold catabolic activity value. The PLC circuit 120 may be operableto supplement the CA1 information with the derivative of CA1 for more amore precise determination of an excess fermentation organism condition.In any case, the PLC circuit 120 is operable to maintain an array ofsuch CA1 data, and to perform conventional regression analyses to trackand predict behavior of this data.

Those skilled in the art will recognize that the foregoing examples areprovided only for the purpose of illustration, and that any one or more,or any combination and/or ratio of, the fermenter 870 operatingparameters in the above list may be monitored and processed by the PLCcircuit 120 to determine whether an excess fermentation organismcondition exists in the fermenter 870. Moreover, the above list may omitone or more of the enumerated items and/or may include one or more otherfermenter 870 operating parameters that are not specifically enumerated,and any such alternative list is intended to fall within the scope ofthe claims appended hereto.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1250, as illustrated in FIG. 26D, for controllingextraction of the fermenting organism, e.g., yeast or other fermentingorganism, from the first fermenter 870 by controlling operation of thefermenting organism extraction pump 1148. The control routine 1250begins at step 1252 where the PLC circuit 120 is operable to estimatethe quantity, Q1, of the fermenting organism collected within the lowerportion of the cone 890. The PLC circuit 120 may be operable at step1250 to estimate the quantity, Q1, of collected fermenting organismwithin the lower portion of the cone 980 according to any one or more ofa number of estimation strategies. For example, Q1 may be estimated as afunction of the amount of time that has elapsed since the fermentingorganism was last extracted from the fermenter 870. As another example,Q1 may be estimated as a function of the change in conductivity of thebiomaterial waste across the fermenter 870. In this embodiment, theroutine 1250 will include a number of steps prior to step 1252 whereinthe PLC circuit 120 is operable to determine the conductivity of thebiomaterial waste entering the fermenter 870 by monitoring the output ofthe conductivity sensor 122 ₁₇, to determine the conductivity of thebiomaterial waste exiting the fermenter 870 by monitoring the output ofthe conductivity sensor 122 ₂₂, and to estimate Q1 as a function of thecorresponding input and output conductivity values. Those skilled in theart will recognize other strategies for estimating the quantity, Q1, ofcollected fermenting organism within the lower portion of the cone 890of the fermenter 870, and any such other strategies are intended to fallwithin the scope of the claims appended hereto.

In any case, execution of the routine 1250 advances from step 1252 tostep 1254 where the PLC circuit 120 is operable to compare Q1 to athreshold fermenting organism quantity, Q1 _(TH). If Q1 is greater thanor equal to Q1 _(TH), algorithm execution advances to step 1256. If,however, the PLC circuit 120 determines at step 1254 that Q1 is lessthan Q1 _(TH), execution of the routine 1250 loops back to step 1252.

At step 1256, the PLC circuit 120 is operable to reset an F1 extractiontimer. Thereafter at step 1258, the PLC circuit 120 is operable toactivate the F1 extraction pump 1148 by appropriately controlling thecorresponding pump driver 1150, and thereafter at step 1260 the PLCcircuit 120 is operable to continually re-execute step 1260 until the F1extraction timer has timed out. The timeout duration of the F1extraction timer may be established according to any one or more of anumber of timer strategies. For example, the timeout period of the F1extraction timer may be set to a constant value based on the physicaldimensions of the fermenter 870 and the cone 890, the composition andflow rate of the biomaterial waste, type of fermenting organism and/orother factors. As another example, the timeout period of the F1extraction timer may be set as a function of the amount of time that haselapsed since the fermenting organism was last collected. As yet anotherexample, the timeout period of the F1 extraction timer may be set as afunction of the estimated quantity, Q1, of the fermenting organismcollected within the lower portion of the cone 890. Those skilled in theart will recognize other strategies for determining an appropriate timeout period of the F1 extraction timer, and any such other strategies areintended to fall within the scope of the claims appended hereto. In anycase, execution of the routine 1250 advances from the “yes” branch ofstep 1260 to step 1262 where the PLC circuit 120 is operable todeactivate the F1 extraction pump 1148. Thereafter, execution of theroutine 1250 loops back to step 1252.

As an alternative to steps 1256-1260, the routine 1250 may insteadinclude steps 1266-1270 as shown encompassed within dashed-line box 1264in FIG. 26D. In this embodiment execution of the routine 1250 advancesfrom the “yes” branch of step 1254 to step 1266 where the PLC circuit120 is operable to activate the F1 extraction pump 1148 by appropriatelycontrolling the corresponding pump driver 1150. Thereafter at step 1268,the PLC circuit 120 is operable to determine an operating torque of theF1 extraction pump 1148. In this embodiment, the pump driver 1150includes an output signal path 124 ₃₃ as shown in phantom in FIG. 25,and the pump driver 1150 is operable to determine an operating torque ofthe pump 1148 using any one or more of the techniques described herein,and produce a corresponding operating torque signal, F1T, on signal path124 ₃₃. The PLC circuit 120 is operable at step 1268 to determine theoperating torque of the F1 extraction pump 1148 by monitoring the outputtorque signal, F1T, on signal path 124 ₃₃, and execution of the routine1250 advances therefrom to step 1270 where the PLC circuit 120 isoperable to compare F1T to a torque threshold F1T_(TH). As long as F1Tis greater than F1T_(TH), execution of the routine 1250 loops back tostep 1268. If the PLC circuit 120 determines at step 1270 that F1T isless than or equal to F1T_(TH), execution of the routine 1250 advancesto step 1262. In the illustrated embodiment, F1T_(TH) is set at a torquevalue below which the quantity of fermenting organism collected in thelower portion of the cone 890 has been sufficiently extracted.

The PLC circuit 120 is operable, under the direction of the routine1250, to selectively extract the fermenting organism collected withinthe lower portion of the cone 890 of the fermenter 870 by estimating thequantity of fermenting organism collected within the lower portion ofthe cone 890 and controlling the F1 extraction pump 1148 to extract thefermenting organism from the cone 890 when the estimated fermentingorganism quantity is greater than or equal to a threshold quantity. Inone embodiment, activation of the F1 extraction pump 1148 is controlledon a timed basis, and in an alternative embodiment activation of the F1extraction pump 1148 is controlled as a function of the output torque ofthe pump 1148. In either case, collection and extraction of thefermenting organism within/from the fermenter 870 are asynchronousoperations, and the routines 1228 and 1250 may accordingly be executedsimultaneously or non-simultaneously.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1280, as illustrated in FIG. 26E, for controlling theliquid level within the second fermenter 910. The control routine 1280begins at step 1282 where the PLC circuit 120 is operable to determinethe operating pressure, P3, of the second fermenter 910 by monitoringthe pressure signal produced by the pressure sensor 122 ₂₈ on signalpath 124 ₂₈. Thereafter at step 1284, the PLC circuit 120 is operable todetermine the pressure, P4, of gas exiting the second fermenter 910 bydetermining the set point of the mechanical pressure control valve 1136.Following step 1284, the PLC circuit 120 is operable at step 1286 tocompare the difference between P3 and P4 to a design pressure, P_(DES2),where P_(DES2) corresponds to a pressure equivalent of the desiredliquid level within the second fermenter 910.

If, at step 1286, the PLC circuit 120 determines that (P3−P4) is greaterthan P_(DES2), indicating that the liquid level within the secondfermenter 910 is higher than desired, the PLC circuit 120 is operablethereafter at step 1288 to increase the speed of the residual liquidoutlet pump 1144 by producing an appropriate actuator control signal onsignal path 130 ₂₁, to increase the flow of liquid exiting the secondfermenter 910. If, on the other hand, the PLC circuit 120 determines atstep 1286 that (P3−P4) is not greater than P_(DES2), execution of thecontrol routine 1280 advances to step 1290 where the PLC circuit 120 isagain operable to compare the difference between P3 and P4 to the designpressure, P_(DES2). If, at step 1290, the PLC circuit determines that(P3−P4) is less than P_(DES2), indicating that the liquid level withinthe second fermenter 910 is lower than desired, the PLC circuit 120 isoperable thereafter at step 1292 to decrease the speed of the residualliquid outlet pump 1144 by producing an appropriate actuator controlsignal on signal path 130 ₂₁, to decrease the flow of liquid exiting thesecond fermenter 910. If, on the other hand, the PLC circuit 120determines at step 1290 that (P3−P4) is not less than P_(DES2),execution of the control routine 1280 loops back to step 1282 as it alsodoes following execution of steps 1288 and 1292.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1300, as illustrated in FIG. 26F, for controlling theoperating temperature of the second fermenter 910 by controlling thetemperature of the liquid waste entering the second fermenter 910 fromthe first fermenter 870 via control of coolant fluid flow through theheat exchanger HX4. The control routine 1300 begins at step 1302 wherethe PLC circuit 120 is operable to determine the flow rate of coolantfluid, CF4, from the cooling tower unit 586 through the heat exchangerHX4. In the illustrated embodiment, the PLC 120 is operable to executestep 1302 by computing CF4 as a function of the flow rate of thebiomaterial waste entering the second fermenter 910, via conduit 900,from the first fermenter 870, the temperature difference between thebiomaterial waste entering and exiting HX4 and the temperaturedifference between the cooling fluid entering and exiting HX4. Inparticular, the PLC 120 is operable at step 1302 to compute CF4according to the equation CF4=F122 ₂₁*(T122 ₁₄−T122 ₂₃)/(T122 ₂₆−T122₂₇), where F122 ₂₁ is the biomaterial waste flow rate signal produced bythe flow sensor 122 ₂₁, T122 ₁₄ is the temperature signal produced bythe temperature sensor 122 ₁₄ on signal path 124 ₁₄ and represents theoperating temperature of the first fermenter 870 and thus thetemperature of the biomaterial waste entering HX4, T122 ₂₃ is thetemperature signal produced by the temperature sensor 122 ₂₃ on signalpath 124 ₂₃ and represents the temperature of the biomaterial wasteexiting HX4, T122 ₂₆ is the temperature signal produced by thetemperature sensor 122 ₂₆ on signal path 124 ₂₆ and represents thetemperature of the cooling fluid entering HX4 from the cooling towerunit 586, and T122 ₂₇ is the temperature signal produced by thetemperature sensor 122 ₂₇ on signal path 124 ₂₇ and represents thetemperature of the cooling fluid exiting HX4. Alternatively, the coolantflow path through HX4 may include a flow meter or sensor, and in thisembodiment the PLC 120 may be operable to execute step 1302 bymonitoring the flow signal produced by such a flow meter or sensor. Inany case, the execution of routine 1300 advances from step 1302 to step1304 where the PLC circuit 120 is operable to determine the operatingtemperature, T2, of the second fermenter 910 by monitoring thetemperature signal produced by the temperature sensor 122 ₂₉ on signalpath 124 ₂₉. Thereafter at step 1306, the PLC circuit 120 is operable tocompare the temperature, T2, of the second fermenter 910 to a designtemperature, T_(D2), wherein T_(D2) corresponds to a desired operatingor fermenting temperature of the second fermenter 910.

If, at step 1306, the PLC circuit 120 determines that T2 is greater thanT_(D2), indicating that the operating temperature of the secondfermenter 910 is greater than the design temperature, T_(D2), executionof the control routine 1300 advances to step 1308 where the PLC circuit120 is operable to compare the cooling fluid flow rate, CF4, through HX4to a maximum flow rate value, MAXF4, wherein MAXF4 corresponds to adesired maximum flow rate of cooling fluid from the cooling tower unit586. If, at step 1308, the PLC circuit 120 determines that CF4 isgreater than or equal to MAXF4, routine execution advances to step 1310where the PLC circuit 120 is operable to decrease the flow ofbiomaterial waste to the fermentation unit 580. In one embodiment, thePLC circuit 120 is operable to execute step 1310 by decreasing the speedof the biomaterial waste pump 612 forming part of the sterilization unit570 as illustrated in FIG. 13A. Alternatively or additionally, the PLCcircuit 120 may be operable to execute step 1310 by controlling thediverter valve 638 of the sterilization unit 570 to divert at least someof the biomaterial waste stream exiting the sterilization loop 630 backthrough the sterilization unit 570 to thereby decrease the flow rate ofbiomaterial waste exiting the sterilization unit 570. Alternatively oradditionally still, the PLC circuit 120 may be operable to execute step1310 by controlling the biomaterial waste return valve 622 to return atleast some of the biomaterial waste stream flowing through thesterilization unit 570 back to the biomaterial waste source 20 (FIG. 1)to thereby decrease the flow rate of biomaterial waste exiting thesterilization unit 570. In any case, execution of the routine 1300 loopsfrom step 1310 back to step 1302.

If, at step 1308, the PLC circuit 120 determines that the CF4 is lessthan MAXF4, routine execution advances to step 1312 where the PLCcircuit 120 is operable to compare the speed of the pump 1132 (P4)supplying the cooling fluid from the cooling tower unit 586 to HX4 to amaximum pump speed, MAXSP4, wherein MAXSP4 corresponds to a maximum pumpspeed value that may be arbitrary or may be dictated by the physicalproperties of the pump 1132. In either case, if the PLC circuit 120determines at step 1312 that the speed of the pump P4 is greater than orequal to MAXSP4, routine execution advances to step 1314 where the PLCcircuit 120 is operable to stop the flow of biomaterial waste to thefermentation unit 580. In one embodiment, the PLC circuit 120 isoperable to execute step 1314 by deactivating the biomaterial waste pump612 forming part of the sterilization unit 570 as illustrated in FIG.13A. Alternatively or additionally, the PLC circuit 120 may be operableto execute step 1314 by controlling the diverter valve 638 of thesterilization unit 570 to divert the biomaterial waste stream exitingthe sterilization loop 630 back through the sterilization unit 570 tothereby stop the flow rate of biomaterial waste exiting thesterilization unit 570. Alternatively or additionally still, the PLCcircuit 120 may be operable to execute step 1310 by controlling thebiomaterial waste return valve 622 to return the biomaterial wastestream flowing through the sterilization unit 570 back to thebiomaterial waste source 20 (FIG. 1) to thereby stop the flow rate ofbiomaterial waste exiting the sterilization unit 570. In any case,execution of the routine 1300 advances from step 1314 to step 1318 wherethe PLC circuit 120 is operable to pause until the temperature, T2, ofthe fermenter 910 is less than or equal to the design temperature, TD2.Thereafter, routine execution advances to step 1320 where the controlcircuit is operable to control the flow of the biomaterial waste streamentering the fermentation unit 580, using any of the techniques justdescribed, to resume the flow of biomaterial waste into the fermentationunit 580. Thereafter, execution of the routine 1300 loops back to step1302. If, at step 1312, the PLC circuit 120 determines that the speed ofthe cooling fluid pump P4 is less than MAXSP4, routine executionadvances to step 1316 where the PLC circuit 120 is operable to increasethe speed of the pump P4 by appropriately controlling the pump driver1134. Thereafter, routine execution loops back to step 1302.

If, at step 1306, the PLC circuit 120 determines that the temperature,T2, of the fermenter 910 is greater than the design temperature, TD2,routine execution advances to step 1322 where the PLC circuit 120 isoperable to determine whether T2 is less than TD2. If not, then T2=TD2and routine execution advances to step 1324 where the PLC circuit 120 isoperable to maintain the current speed of the pump P4 by appropriatelycontrolling the pump driver 1134. If, at step 1322, the PLC circuit 120determines that T2 is less than TD2, routine execution advances to step1326 where the PLC circuit 120 is operable to decrease the speed of thepump P4 by appropriately controlling the pump driver 1134. Routineexecution loops from either of steps 1324 and 1326 back to step 1302.

The PLC circuit 120 is operable, under the direction of the routine1300, to control the temperature, T2, of the second fermenter 910 bycomparing T2 to a design temperature, TD2, and increasing the speed ofthe pump 1132 (P4) supplying cooling fluid from the cooling tower unit586 to the heat exchanger HX4 if T2 is greater than TD2, the flow rateof the cooling fluid through HX4 is less than a maximum cooling fluidflow rate, MAXF4, and the speed of the pump 1132 is not greater than orequal to a maximum pump speed, MAXSP4. If, however, T2 is greater thanTD2 and the flow rate of the cooling fluid through HX4 is greater thanor equal to MAXF4, then T2 cannot be lowered by increasing the speed ofthe pump 1132, and the flow rate of the biomaterial waste into thefermentation unit 580 is instead decreased. If T2 is greater than TD2and the flow rate of the cooling fluid through HX4 is less than MAXF4but the speed of the pump 1132 is greater than or equal to the maximumpump speed, MAXSP4, then no action of the cooling fluid pump 1132 willresult in further cooling of the biomaterial waste stream, and in thiscase the flow of biomaterial waste into the fermentation unit 580 isstopped until T2 becomes less than or equal to TD2. If T2 is less thanTD2, the speed of the pump 1132 is decreased, and if T2 is equal to TD2the speed of the pump 1132 is maintained at its current pump speed.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1328, as illustrated in FIG. 26G, for controllingcollection of the fermenting organism, e.g., yeast or other fermentingorganism, within the lower portion of the cone 930 of the secondfermenter 910 as illustrated in FIGS. 19, 21-22 and 24A-24C. It will beunderstood that the control routine 1328 represents one embodiment of acontrol routine for controlling fermenting organism collection withinthe fermenter 910 during normal, continuous flow operation, and that airflow into the outer and inner air spargers 904 and 934 respectively ofthe fermenter 910 will typically be established and controlled prior tonormal, continuous flow operation by the PLC circuit 120. The controlroutine 1328 begins at step 1330 where the PLC circuit 120 is operableto determine the flow rate of air exiting the fermenter 910 bymonitoring the mass air flow signal produced by the mass flow meter orsensor 122 ₃₀ illustrated in FIG. 25. Thereafter at step 1332, the PLCcircuit 120 is operable to control the inner sparger inlet valve 1128and outer sparger inlet valve 1126 respectively of the fermenter 910 todrive the mass flow rate of air exiting the fermenter 910 to a designmass air flow exit value, F2AED, wherein F2AED represents a target massair flow value that will depend, at least in part, on the physicaldimensions of the fermenter 910, the flow rate of the biomaterial wastethrough the fermentation unit 580, the type of biomaterial waste andother factors.

Following step 1332, the PLC circuit 120 is operable at step 1334 tomonitor one or more excess fermentation organism indicators, F2E.Following step 1334, the PLC circuit 120 is operable at step 1336 todetermine whether the one or more excess fermentation organismindicators, F2E, indicate an excess of the fermentation organism withinthe fermenter 910. If not, the routine 1328 continually loops back tostep 1334 until F2E indicates a fermentation organism excess. When thePLC circuit 120 determines at step 1336 that F2E indicates afermentation organism excess, execution of the routine 1328 advances tostep 1338. Details relating to some example strategies for determiningwhen a fermentation organism excess condition exists according to steps1334 and 1336 will be described hereinafter following the description ofthe general steps of the routine 1328.

At step 1338, the PLC circuit 120 is operable to reset a fermentationorganism collection timer. Thereafter at step 1340, the PLC circuit 120is operable to control the inner sparger inlet valve 1128 to a closedposition to stop the flow of air to the inner sparger 934 of thefermenter 910. Thereafter at step 1342, the PLC circuit 120 is operableto determine the mass flow rate, F2AE, of air exiting the fermenter 910by monitoring the mass flow rate signal produced by the mass flow meteror sensor 122 ₃₀, and at the following step 1344 the PLC circuit 120 isoperable to control the outer sparger inlet valve 1126 to increase theair flow to the outer sparger 904 to compensate for turning off the flowof air to the inner sparger 934 at step 1340. In the illustrativeembodiment of routine 1328, it is desirable to maintain constant massair flow through the fermenter 910, and the PLC circuit 120 isaccordingly operable at step 1344 to control the outer sparger inletvalve 1126 to increase the air flow to the outer sparger 904 to an airflow level that maintains the mass air flow exiting the fermenter 910 ata constant level. Following step 1344, the PLC circuit 120 is operableat step 1346 to continually loop back to step 1346 until the F2collection timer has timed out. Thereafter at step 1348, the PLC circuitis operable to return the positions of the outer and inner air spargers904 and 934 respectively of the fermenter 910 to their pre-collectionvalve positions. Execution of the routine loops from step 1348 back tostep 1330.

By stopping the flow of air to the inner sparger 934 of the fermenter910 at step 1340 the fermenting organism present in and above the cone930 settles, and is collected within, the lower portion of the cone 930,thereby reducing the total amount of the fermentation organism beingcirculated through the fermenter 910. In the illustrated embodiment,airflow to the inner sparger 934 of the fermenter 910 is turned off fora time period defined by the timeout duration of the F2 collectiontimer. The timeout duration of the F2 collection timer may beestablished according to any one or more of a number of timerstrategies. For example, the timeout period of the F2 collection timermay be set to a constant value based on the physical dimensions of thefermenter 910, composition and flow rate of the biomaterial waste, typeof fermenting organism and/or other factors. As another example, thetimeout period of the F2 collection timer may be set as a function ofthe amount of time that has elapsed since the fermenting organism waslast collected. As yet another example, the timeout period of the F2collection timer may be set as a function of the change in conductivityof the biomaterial waste across the fermenter 910. In this embodiment,the routine 1328 will include a number of steps between steps 1344 and1346 wherein the PLC circuit 120 is operable to determine theconductivity of the biomaterial waste entering the fermenter 910 bymonitoring the output of the conductivity sensor 122 ₂₂, to determinethe conductivity of the biomaterial waste exiting the fermenter 910 bymonitoring the output of the conductivity sensor 122 ₃₂, and todetermine the timeout period of the F2 collection timer, correspondingto the time that the inner sparger 934 is turned off, as a function ofthe corresponding input and output conductivity values. Those skilled inthe art will recognize other strategies for determining an appropriatetime out period of the F2 collection timer, and any such otherstrategies are intended to fall within the scope of the claims appendedhereto. In any case, the fermenting organism is collected within thelower portion of the cone 930 such that when air flow to the innersparger 934 is thereafter restored, the fermenting organism collectedwithin the lower portion of the cone 930 remains in the lower portion ofthe cone 930 for subsequent extraction.

The PLC circuit 120 is generally operable to execute steps 1334 and 1336to determine whether an excess amount of the fermenting organism existsin the fermenter 910 by monitoring and processing one or more operatingparameters of the fermenter 910. Particular ones or combinations of theoperating parameters of the fermenter 910 used to determine whether anexcess of the fermenting organism exists in the fermenter 910 willdepend on a number of factors including, but not limited to, thephysical dimensions of the fermenter 910, the composition and flow rateof the biomaterial waste, the type of fermenting organism, and the like.As one illustrative example, the following list represents one or moreparameters that may be monitored to determine whether an excess amountof the fermenting organism exists in the fermenter 910 in the case wherethe fermenter 910 has the physical dimensions given by example inreference to FIGS. 24A-24C, where the biomaterial waste is cattle wastehaving variable nutrient content, and where the flow rate of the cattlewaste through the fermenter 910 is approximately 100 gallons (379liters) per minute:

1. mass flow rate of gas (air) exiting the fermenter 910,

2. derivative of 1,

3. change, e.g., decrease, in conductivity across the fermenter 910,

4. derivative of 2,

5, BTU generated in the fermenter 910, and

6. ratios of one or more combinations of 1-5.

Those skilled in the art will recognize that the foregoing list may omitone or more items and/or include other operating parameters notspecifically listed, and that any such alternate list will typically bedictated by the specific application of the biomaterial waste processingsystem 10.

In the illustrated example, the fermenter 910 is sized to supply moreincoming air than is required to support fermentation therein.Consequently, the fermenter 910 will typically not use all of the airsupplied to it. As a result, the mass flow rate of gas (air) exiting thefermenter 910 will typically not be a highly sensitive indicator ofexcess fermenting organism in the fermenter 910. However, in otherembodiments of the fermentation unit 580, the fermenter 910 may be sizedand configured similarly as described hereinabove with respect to thefermenter 870, and in such cases the mass flow rate of gas (air) exitingthe fermenter 910 may be a sensitive indicator of excess fermentingorganism in the fermenter 910. In such cases, the PLC circuit 120 isoperable as described hereinabove with respect to the control routine1200 of FIG. 26C at steps 1332 and 1334 to determine whether an excessof the fermentation organism exists in the fermenter 910 by monitoringthe mass flow rate of gas (air) exiting the fermenter 910 and advancingto step 1238 if the exit gas mass flow rate increases above a ratio ofthe exit gas mass flow rate and a baseline exit gas mass flow rate,which may be calculated prior to fermentation within the secondfermenter 910 in a similar manner to that described hereinabove withrespect to control routine 1228 of FIG. 26C, or above a derivative ofthe baseline exit gas mass flow rate value for the second fermenter 910.

Similarly as described hereinabove with respect to the fermenter 870,the heat (BTU) generated by the metabolic activity within the fermenter910 is given by the equation BTU=F122 ₂₁*(TD2−T122 ₂₃), where F122 ₂₁ isthe biomaterial waste flow rate signal produced by the flow sensor 122₂₁, TD2 is the design fermentation temperature of the fermenter 910, andT122 ₂₃ is the temperature signal produced by the temperature sensor 122₂₃ on signal path 124 ₂₃ and represents the temperature of thebiomaterial waste exiting HX4 and entering the fermenter 910. BTU isalso the sum of the catabolic activity and the anabolic activity withinthe fermenter 910, where the difference in the conductivity across thefermenter 910 is a direct measure of the anabolic activity, e.g.,anabolic activity=K*(C122 ₂₂−C122 ₃₂), where K is a constant, C122 ₂₂ isthe conductivity signal produced by the conductivity sensor 122 ₂₂ andrepresents the conductivity of the biomaterial waste entering thefermenter 910, and C122 ₃₂ is the conductivity signal produced by theconductivity sensor 122 ₃₂ and represents the conductivity of thebiomaterial waste exiting the fermenter 910. The catabolic activity,CA2, within the fermenter 910 is then the difference between the BTUvalue and the anabolic activity according to the equation CA2=F122₂₁*(TD1−T122 ₂₃)−K*(C122 ₂₂−C122 ₃₂). In this example, the PLC circuit120 is operable at steps 1332 and 1334 to determine whether an excess ofthe fermentation organism exists in the fermenter 910 by computing thecatabolic activity, CA2, according to the above equation and advancingto step 1338 if CA2 falls below a threshold catabolic activity value.The PLC circuit 120 may be operable to supplement the CA2 informationwith the derivative of CA2 for more a more precise determination of anexcess fermentation organism condition. In any case, the PLC circuit 120is operable to maintain an array of such CA2 data, and to performconventional regression analyses to track and predict behavior of thisdata. In the illustrated example, the catabolic activity data is ahighly sensitive indicator of excess fermenting organism in thefermenter 910.

Those skilled in the art will recognize that the foregoing examples areprovided only for the purpose of illustration, and that any one or more,or any combination and/or ratio of, the fermenter 910 operatingparameters in the above list may be monitored and processed by the PLCcircuit 120 to determine whether an excess fermentation organismcondition exists in the fermenter 910. Moreover, the above list may omitone or more of the enumerated items and/or may include one or more otherfermenter 910 operating parameters that are not specifically enumerated,and any such alternative list is intended to fall within the scope ofthe claims appended hereto.

The fermentation unit control algorithm 1180 further includes anothercontrol routine 1350, as illustrated in FIG. 26H, for controllingextraction of the fermenting organism, e.g., yeast or other fermentingorganism, from the second fermenter 910 by controlling operation of thefermenting organism extraction pump 1158. The control routine 1350begins at step 1352 where the PLC circuit 120 is operable to estimatethe quantity, Q2, of the fermenting organism collected within the lowerportion of the cone 930. The PLC circuit 120 may be operable at step1350 to estimate the quantity, Q2, of collected fermenting organismwithin the lower portion of the cone 930 according to any one or more ofa number of estimation strategies. For example, Q2 may be estimated as afunction of the amount of time that has elapsed since the fermentingorganism was last extracted from the fermenter 910. As another example,Q2 may be estimated as a function of the change in conductivity of thebiomaterial waste across the fermenter 910. In this embodiment, theroutine 1350 will include a number of steps prior to step 1352 whereinthe PLC circuit 120 is operable to determine the conductivity of thebiomaterial waste entering the fermenter 910 by monitoring the output ofthe conductivity sensor 122 ₂₂, to determine the conductivity of thebiomaterial waste exiting the fermenter 910 by monitoring the output ofthe conductivity sensor 122 ₃₂, and to estimate Q2 as a function of thecorresponding input and output conductivity values. Those skilled in theart will recognize other strategies for estimating the quantity, Q2, ofcollected fermenting organism within the lower portion of the cone 930of the fermenter 910, and any such other strategies are intended to fallwithin the scope of the claims appended hereto.

In any case, execution of the routine 1350 advances from step 1352 tostep 1354 where the PLC circuit 120 is operable to compare Q2 to athreshold fermenting organism quantity, Q2 _(TH). If Q2 is greater thanor equal to Q2 _(TH), algorithm execution advances to step 1356. If,however, the PLC circuit 120 determines at step 1354 that Q2 is lessthan Q2 _(TH), execution of the routine 1350 loops back to step 1352.

At step 1356, the PLC circuit 120 is operable to reset an F2 extractiontimer. Thereafter at step 1358, the PLC circuit 120 is operable toactivate the F2 extraction pump 1158 by appropriately controlling thecorresponding pump driver 1160, and thereafter at step 1360 the PLCcircuit 120 is operable to continually re-execute step 1360 until the F2extraction timer has timed out. The timeout duration of the F2extraction timer may be established according to any one or more of anumber of timer strategies. For example, the timeout period of the F2extraction timer may be set to a constant value based on the physicaldimensions of the fermenter 910 and the cone 930, the composition andflow rate of the biomaterial waste, type of fermenting organism and/orother factors. As another example, the timeout period of the F2extraction timer may be set as a function of the amount of time that haselapsed since the fermenting organism was last collected. As yet anotherexample, the timeout period of the F2 extraction timer may be set as afunction of the estimated quantity, Q2, of the fermenting organismcollected within the lower portion of the cone 930. Those skilled in theart will recognize other strategies for determining an appropriate timeout period of the F2 extraction timer, and any such other strategies areintended to fall within the scope of the claims appended hereto. In anycase, execution of the routine 1350 advances from the “yes” branch ofstep 1360 to step 1362 where the PLC circuit 120 is operable todeactivate the F2 extraction pump 1158. Thereafter, execution of theroutine 1350 loops back to step 1352.

As an alternative to steps 1356-1360, the routine 1350 may insteadinclude steps 1366-1370 as shown encompassed within dashed-line box 1364in FIG. 26H. In this embodiment execution of the routine 1350 advancesfrom the “yes” branch of step 1354 to step 1366 where the PLC circuit120 is operable to activate the F2 extraction pump 1158 by appropriatelycontrolling the corresponding pump driver 1160. Thereafter at step 1368,the PLC circuit 120 is operable to determine an operating torque of theF2 extraction pump 1158. In this embodiment, the pump driver 1160includes an output signal path 124 ₃₂ as shown in phantom in FIG. 25,and the pump driver 1160 is operable to determine an operating torque ofthe pump 1158 using any one or more of the techniques described herein,and produce a corresponding operating torque signal, F2T, on signal path124 ₃₂. The PLC circuit 120 is operable at step 1368 to determine theoperating torque of the F2 extraction pump 1158 by monitoring the outputtorque signal, F2T, on signal path 124 ₃₂, and execution of the routine1350 advances therefrom to step 1370 where the PLC circuit 120 isoperable to compare F2T to a torque threshold F2T_(TH). As long as F2Tis greater than F2T_(TH), execution of the routine 1350 loops back tostep 1368. If the PLC circuit 120 determines at step 1370 that F2T isless than or equal to F2T_(TH), execution of the routine 1350 advancesto step 1362. In the illustrated embodiment, F2T_(TH) is set at a torquevalue below which the quantity of fermenting organism collected in thelower portion of the cone 930 has been sufficiently extracted.

The PLC circuit 120 is operable, under the direction of the routine1350, to selectively extract the fermenting organism collected withinthe lower portion of the cone 930 of the fermenter 910 by estimating thequantity of fermenting organism collected within the lower portion ofthe cone 930 and controlling the F2 extraction pump 1158 to extract thefermenting organism from the cone 930 when the estimated fermentingorganism quantity, Q2, is greater than or equal to a threshold quantity.In one embodiment, activation of the F2 extraction pump 1158 iscontrolled on a timed basis, and in an alternative embodiment activationof the F2 extraction pump 1158 is controlled as a function of the outputtorque of the pump 1158. In either case, collection and extraction ofthe fermenting organism within/from the fermenter 910 are asynchronousoperations, and the routines 1328 and 1350 may accordingly be executedsimultaneously or non-simultaneously.

Referring now to FIG. 27A, a schematic diagram of one illustrativeembodiment of the pasteurization unit 594 and corresponding controlsystem that forms part of the waste fermentation system of FIG. 12 isshown. In the illustrated embodiment, the conduit 598 that is fluidlycoupled to the product inlet, PIP, of the pasteurization unit 594 passesthrough a first ball valve, BV, through a pasteurization heat exchangerHX6, through another pair of ball valves, BV, through apost-pasteurization heat exchanger HX7, and through another pair of ballvalves, BV, to a fermenting organism product port of a fermentingorganism product storage tank 1400. The fermenting organism productstorage tank 1400 is, in the illustrated embodiment, an insulated tankof known construction and operable to maintain the temperature of thefermenting organism product supplied thereto near the temperature of thefermenting organism product exiting the post-pasteurization heatexchanger 1400. Alternatively, the fermenting organism product tank 1400may include conventional temperature controls for controlling thetemperature of the tank interior and its contents.

In any case, the pasteurization unit 594 further includes a conventionalagitator 1402 configured to agitate or stir the fermenting organismproduct stored in the tank 1400. The agitator 1402 represents one of the“Q” actuators of the pasteurization unit 594, and is electricallyconnected to one of the actuator outputs of the PLC circuit 120 via oneof the “Q” signal paths 130 ₂₆. The PLC circuit 120 is operable toperiodically control the agitator 1402 for a predefined time period byproducing an appropriate signal on signal path 130 ₂₆ to periodicallystir the fermenting organism product stored within the fermentingorganism product storage tank 1400. One of the “R” sensors includedwithin the pasteurization unit 594 is a conventional temperature sensor122 ₃₄ disposed in fluid communication with the interior of thefermenting organism product storage tank 1400 and electrically connectedto the PLC circuit 120 via one of the “R” signal paths 124 ₃₄. Thetemperature sensor 122 ₃₄ is operable to produce a temperature signal onsignal path 124 ₃₄ indicative of the temperature of the fermentingorganism product stored in the fermenting organism product storage tank1400. In the illustrated embodiment, the PLC circuit 120 is configuredto monitor the temperature signal produced by the temperature sensor 122₃₄ on signal path 124 ₃₄, and to activate a warning mechanism if thetemperature within the fermenting organism product storage tank risesabove a threshold temperature level. If this occurs, a technician mayextract the fermenting organism product stored in the tank 1400 andsuitably relocate the product. Alternatively, in embodiments wherein thefermenting organism product storage tank 1400 includes temperaturecontrols, the PLC circuit 120 may be configured to adjust suchtemperature controls as a function of the temperature signal produced bythe temperature sensor 122 ₃₄ on signal path 124 ₃₄ to maintain thefermenting organism product stored in the tank 1400 near a desiredstorage temperature.

The conduit 604 that is fluidly coupled to the pasteurization steaminlet, PSTI, is coupled through a steam control valve 1404, through aball valve, BV, through a steam-to-water heat exchanger HX5, throughanother ball valve, BV, and then fluidly coupled to conduit 606 todefine the pasteurization steam outlet, PSTO, of the pasteurization unit594. The steam control valve 1404 represents another one of the “Q”actuators of the pasteurization unit 594, and is electrically connectedto another one of the actuator outputs of the PLC circuit 120 via one ofthe “Q” signal paths 130 ₂₇. Another conduit 1414 passes through theopposite side of the steam-to-water heat exchanger HX5 and passesthrough a pair of ball valves, BV, to the pasteurization heat exchangerHX6, and from HX6 through another ball valve, BV, to an inlet of a waterstorage tank 1406 configured to store a quantity of water therein. Anoutlet of the water storage tank 1406 is coupled through a pair of ballvalves, BV, to an inlet of a water pump 140 ₁₀ having a pump outletcoupled through another pair of ball valves, BV, through HX5 via conduit1414. A conventional pump driver 1412 is electrically connected to thewater pump 1410. The pump driver 1412 represents another one of the “Q”actuators of the pasteurization unit 594, and is electrically connectedto another one of the actuator outputs of the PLC circuit 120 via one ofthe “Q” signal paths 130 ₂₈. Another one of the “R” sensors includedwithin the pasteurization unit 594 is another conventional temperaturesensor 122 ₃₅ disposed in fluid communication with the conduit 1414between the heat exchangers HX5 and HX6 and electrically connected tothe PLC circuit 120 via one of the “R” signal paths 124 ₃₅. Thetemperature sensor 122 ₃₅ is operable to produce a temperature signal onsignal path 124 ₃₅ indicative of the temperature of the steam heatedwater exiting the steam-to-water heat exchanger HX5.

In the illustrated embodiment, the water conduit 26 fluidly coupled tothe water inlet, WI, of the pasteurization unit 594 is coupled throughan inlet control valve 1416 and a ball valve, BV, and passes through anopposite side of the post-pasteurization heat exchanger HX7 and anotherball valve, BV, and then intersects the waste return outlet conduit 596defining the waste return outlet, WRO, of the pasteurization unit 594.The inlet control valve 1416 represents another one of the “Q” actuatorsof the pasteurization unit 594, and is electrically connected to anotherone of the actuator outputs of the PLC circuit 120 via another one ofthe “Q” signal paths 130 ₂₉. Another one of the “R” sensors includedwithin the pasteurization unit 594 is another conventional temperaturesensor 122 ₃₆ disposed in fluid communication with the heat exchangerHX7 and electrically connected to the PLC circuit 120 via one of the “R”signal paths 124 ₃₆. The temperature sensor 122 ₃₆ is operable toproduce a temperature signal on signal path 124 ₃₆ indicative of thetemperature of the post-pasteurization heat exchanger HX7. Inembodiments wherein the temperature of the water supplied by theconventional water system 24 to the post-pasteurization heat exchangerHX7 via conduit 26 is not low enough to sufficiently cool thepasteurized fermenting organism flowing through HX7, cooling fluid fromthe cooling tower unit 586 (see FIG. 17) may instead be circulatedthrough the post-pasteurization heat exchanger HX7 via conduits 590 and588. Alternatively still, the pasteurization unit 594 may include adedicated cooling tower unit, similar or identical in operation to thecooling tower unit 586 illustrated in FIG. 17, to provide water or othercooling fluid to the post-pasteurization heat exchanger HX7 at atemperature low enough to sufficiently cool the pasteurized fermentingorganism flowing through HX7.

The conduit 598 fluidly coupled to the fermenting organism productstorage tank 1400 is fluidly connected to one end of another conduit1418 between the two ball valves, BV, separating the fermenting organismproduct storage tank 1400 and the post-pasteurization heat exchangerHX7. The opposite end of the conduit 1418 is fluidly coupled to an inletof a product extraction pump 1420 having an outlet fluidly coupledthrough another ball valve, BVV, to the product outlet, POP, of thepasteurization unit 594 and to the product outlet conduit 70. The outletof the product outlet pump 1420 is also fluidly coupled through anotherball valve, BVW, to the waste return outlet, WRO, of the pasteurizationunit 594. The product outlet pump is electrically connected to aconventional pump driver 1422, which represents another of the “Q”actuators of the pasteurization unit 594, and the pump driver iselectrically connected to another actuator outputs of the PLC 120 viaanother of the “Q” signal paths 130 ₃₀. The PLC circuit 120 is operableto activate the product outlet pump 1420 via an appropriate signal onsignal path 130 ₃₀ whenever it is desirable to extract fermentingorganism product from the fermenting organism product storage tank 1400.The fermenting organism product extracted by the product outlet pump1420 is supplied to the product outlet, POP, when the ball valve BVW isclosed and the ball valve BVV is open. If the ball valve BVV is closedand the ball valve BVW is open, the fermenting organism productextracted by the product outlet pump 1420 is instead directed to thewaste return outlet, WRO, of the pasteurization unit 594. Under normal,fermenting organism collection operation, the product outlet pump is offand the ball valves BVV and BVW are closed.

The junction of conduits 598 and 1418 is also fluidly coupled throughball valves BVY and BVZ to the sample outlet, SMPL, of thepasteurization unit 594, which is fluidly connected to the productsample conduit 600. The outlet of the ball valve BVY and the inlet ofthe ball valve BVZ are fluidly coupled through another ball valve, BVX,to the sample clean steam inlet, SCSI, of the pasteurization unit 594,which is fluidly connected to the sample clean steam conduit 606. Whenit is desired to sample some of the fermenting organism product storedin the fermenting organism product storage tank 1400, the ball valvesBVY and BVZ are opened while the ball valve BVX is closed. This allowsthe fermenting organism product to be drawn from the sample outlet,SMPL, of the pasteurization unit 594. The product sample passageway justdescribed may be cleaned with steam provided by the steam unit 572 viaconduit 606. When the ball valves BVX and BVZ are opened while the ballvalve BVY is closed, steam entering the sample clean steam inlet, SCSI,is directed through valves BVX and BVZ to the sample outlet, SMPL, toclean and sterilize this passageway. Under normal, fermenting organismcollection operation, the ball valves BVX, BVY and BVZ are closed.

The pasteurization unit 594 is operable, under the control of the PLCcircuit 120, to pasteurize the fermenting organism product produced andsupplied by the fermentation unit 580 via appropriate control of theheat exchangers HX5 and HX6, and to then cool the pasteurized fermentingorganism product via appropriate control of HX7 prior to storage of thecooled and pasteurized fermenting organism product in the fermentingorganism product storage tank 1400. The pasteurization unit 594 justdescribed includes a number of additional manually activated ballvalves, BV, as illustrated in FIG. 27A. Such valves are included withinthe pasteurization unit 594 at various locations to allow for bypassingof, and maintenance or replacement of, various components of thepasteurization unit 594.

Referring now to FIG. 27B, a schematic diagram of another illustrativeembodiment of the pasteurization unit 594′ and corresponding controlsystem that forms part of the waste fermentation system of FIG. 12 isshown. The pasteurization unit 594′ is identical in many respects to thepasteurization unit 594 of FIG. 27A, and like numbers are therefore usedto identify like components. In the embodiment illustrated in FIG. 27B,another heat exchanger, HX8, is added to pre-heat the incoming productprior to entrance into the heat exchanger HX6 to thereby decrease theheating requirement of the heat exchanger HX6. In particular, a firstproduct inlet of the heat exchanger HX8 is fluidly coupled to theproduct inlet port, PIP, of the pasteurization unit 594′ via conduit598, and a first product outlet of the heat exchanger HX8 is fluidlycoupled to the product inlet of the heat exchanger HX6 via a conduit1413. The product outlet of the heat exchanger HX6 is fluidly coupled toa second product inlet of the heat exchanger HX8, and a second productoutlet of the heat exchanger HX8 is fluidly coupled to the heatexchanger HX7 via conduit 1415. The heat exchanger HX8 effectivelypre-heats the incoming product, using the heat in the product exitingthe heat exchanger HX6, prior to entrance into the heat exchanger HX6,thereby decreasing the overall heating requirement of the heat exchangerHX6.

Referring now to FIG. 28, a flowchart of one illustrative embodiment ofa software algorithm 1430 for controlling the pasteurization unit 594 ofeither of FIGS. 27A and 27B is shown. It will be understood that thesoftware algorithm 1430 represents one illustrative strategy forcontrolling the pasteurization unit 594 during normal, continuous flowoperation of the biomaterial waste processing system 10, and that thepasteurization unit 594 may be controlled differently during otheroperational modes of the biomaterial waste processing system 10. Thesoftware algorithm 1430 includes a number of different and independentlyexecuting control routines, and each of these different control routineswill be described separately. For example, the control algorithm 1430includes a first control routine 1432 for controlling the temperature ofthe pasteurization heat exchanger HX6. The control routine 1432 beginsat step 1434 where the PLC circuit 120 is operable to determine theoperating temperature, T₆, of the pasteurization heat exchanger HX6 bymonitoring the temperature signal produced by the temperature sensor 122₃₃ on signal path 124 ₃₃. Thereafter at step 1436, the PLC circuit 120is operable to compare T₆ to a target pasteurization temperature, T_(P).If, at step 1436, the PLC circuit 120 determines that T₆ is greater thanor equal to T_(P), execution of the control routine 1432 advances tostep 1438 where the PLC circuit 120 is operable to deactivate the waterpump 1410 if it is currently activated. From step 1438, execution of thecontrol routine 1430 loops back to step 1434.

If, at step 1436, the PLC circuit 120 determines that T₆ is less thanT_(P), then the PLC circuit 120 is operable thereafter at step 1440 toraise the temperature of the pasteurization heat exchanger HX6 byactivating the water pump 1412, by producing an appropriate signal onsignal path 130 ₂₈, to circulate water heated by the heat exchanger HX5between the heat exchangers HX5 and HX6. Thereafter at step 1442, thePLC circuit 120 is operable to determine the temperature, T₅₆, of thewater flowing through conduit 1414 between HX5 and HX6 by monitoring thetemperature signal produced by the temperature sensor 122 ₃₅ on signalpath 124 ₃₅. Following step 1442, the PLC circuit 120 is operable atstep 1444 to compare T₅₆ to a threshold temperature T56 _(TH), whereinT56 _(TH) corresponds to the temperature of the water flowing throughpasteurization heat exchanger HX5 that is required to raise thetemperature of the pasteurization heat exchanger HX5 to or above thetarget pasteurization temperature, T_(P). If, at step 1444, T₅₆ is lessthan T56 _(TH), execution of the control routine 1434 advances to step1446 where the PLC circuit 120 is operable to control the steam inletvalve 1404, by producing an appropriate signal on signal path 130 ₂₇, toincrease the opening of the steam inlet valve 1404 to thereby supplymore steam to the steam-to-water heat exchanger HX5 to raise thetemperature T₅₆. Execution of the control routine 1432 loops from step1446 back to step 1434.

If, at step 1444, the PLC circuit 120 determines that T₅₆ is greaterthan or equal to T56 _(TH), execution of the control routine 1432advances to step 1448 where the PLC circuit 120 is again operable tocompare T₅₆ to T56 _(TH). If, at step 1448, T₅₆ is greater than T56_(TH), execution of the control routine 1434 advances to step 1450 wherethe PLC circuit 120 is operable to control the steam inlet valve 1404,by producing an appropriate signal on signal path 130 ₂₇, to decreasethe opening of the steam inlet valve 1404 to thereby supply less steamto the steam-to-water heat exchanger HX5 to lower the temperature T₅₆.If, however, the PLC circuit 120 determines at step 1448 that T₅₆ is notgreater than T56 _(TH), execution of the control routine 1432 advancesto step 1452 where the PLC circuit 120 is operable to control the steaminlet valve 1404, by producing an appropriate signal on signal path 130₂₇, to maintain the current opening of the steam inlet valve 1404 tothereby maintain the current value of the temperature T₅₆. Execution ofthe control routine 1432 loops from either of steps 1450 and 1452 backto step 1434.

The pasteurization unit control algorithm 1430 further includes anothercontrol routine 1454 for controlling the temperature of thepost-pasteurization heat exchanger HX7. The control routine 1454 beginsat step 1456 where the PLC circuit 120 is operable to determine theoperating temperature, T₇, of the post-pasteurization heat exchanger HX7by monitoring the temperature signal produced by the temperature sensor122 ₃₆ on signal path 124 ₃₆. Thereafter at step 1458, the PLC circuit120 is operable to compare T₇ to a threshold temperature, T7 _(TH),wherein T7 _(TH) corresponds to the temperature of thepost-pasteurization heat exchanger HX7 that is required to cool thepasteurized fermenting organism product flowing therethrough to asuitable storage temperature. If, at step 1458, T₇ is greater than T7_(TH), execution of the control routine 1454 advances to step 1460 wherethe PLC circuit 120 is operable to control the water inlet valve 1416,by producing an appropriate signal on signal path 130 ₂₉, to increasethe opening of the water inlet valve 1416 to thereby supply more freshwater to the heat exchanger HX7 to lower the temperature T₇. Executionof the control routine 1454 loops from step 1460 back to step 1456.

If, at step 1458, the PLC circuit 120 determines that T₇ is greater thanor equal to T7 _(TH), execution of the control routine 1454 advances tostep 1462 where the PLC circuit 120 is again operable to compare T₇ toT7 _(TH). If, at step 1462, T₇ is less than T7 _(TH), execution of thecontrol routine 1454 advances to step 1464 where the PLC circuit 120 isoperable to control the water inlet valve 1416, by producing anappropriate signal on signal path 130 ₂₉, to decrease the opening of thewater inlet valve 1416 to thereby supply less water to the heatexchanger HX5 to raise the temperature T₇. If, however, the PLC circuit120 determines at step 1462 that T₇ is not less than T7 _(TH), executionof the control routine 1454 advances to step 1466 where the PLC circuit120 is operable to control the water inlet valve 1416, by producing anappropriate signal on signal path 130 ₂₉, to maintain the currentopening of the water inlet valve 1416 to thereby maintain the currentvalue of the temperature T₇. Execution of the control routine 1454 loopsfrom either of steps 1464 and 1466 back to step 1456.

Referring now to FIG. 29, a schematic diagram of one illustrativeembodiment of the residual liquid processing unit 16 and correspondingcontrol system that forms part of the biomaterial waste processingsystem 10 of FIG. 1 is shown. In the illustrated embodiment, an inletdiverter valve 1480 has an inlet fluidly coupled to the residual liquidinlet, RLI, of the residual liquid processing unit 16 and to theresidual liquid inlet conduit 74. One outlet of the inlet diverter valve1480 is fluidly coupled via a conduit 1482 to a residual liquid inlet ofa first precipitation tank 1484, and another outlet of the inletdiverter valve 1480 is fluidly coupled via a conduit 1486 to a secondprecipitation tank 1488. The inlet diverter valve 1480 is electricallyconnected to an actuator output of the PLC circuit 140 via signal path150 ₁, and the PLC circuit 140 is operable to control the diverter valve1480, by producing an appropriate signal on signal path 150 ₁, betweenone position fluidly coupling the inlet of the inlet diverter to theinlet diverter valve outlet fluidly coupled to conduit 1482, and anotherposition fluidly coupling the inlet of the inlet diverter valve to theinlet diverter valve outlet fluidly coupled to conduit 486. Theprecipitation tanks 1484 and 1488 are conventional tanks configured toreceive and hold a quantity of liquid therein, and the firstprecipitation tank 1484 includes a level sensor producing a signalindicative of the level of liquid contained therein. Similarly, thesecond precipitation tank 1488 includes a level sensor producing asignal indicative of the level of liquid contained therein. In theillustrated embodiment, these level sensors are provided in the form ofa pressure sensor 142 ₁ disposed in fluid communication with theinterior of the first precipitation tank 1484 and electrically connectedto a sensor input of the PLC circuit 140 via signal path 144 ₁, and apressure sensor 142 ₂ disposed in fluid communication with the interiorof the second precipitation tank 1488 and electrically connected to asensor input of the PLC circuit 140 via signal path 144 ₂. The PLCcircuit 140 is configured to process the signals produced by thepressure sensors 142 ₁ and 142 ₂ and determine corresponding levels ofliquid in the precipitation tanks 1484 and 1488 respectively.Alternatively, one or more other known level sensors may be used withtanks 1484 and 1488 to produce one or more corresponding signalsindicative of the liquid levels in the tanks 1486 and 1488.

A precipitation catalyst solution tank 1490 has a fluid outlet coupledthrough a control valve 1494 to an inlet of a conventional liquid pump1496, and the outlet of the pump 1496 is fluidly coupled to the inlet ofthe inlet diverter valve 1480 via a conduit 1500. The pump 1496 iselectrically connected to a conventional pump driver 1498 that is alsoelectrically connected to an actuator output of the PLC circuit 140 viasignal path 150 ₃. The PLC circuit 140 is configured to control thespeed of the pump 1496 in a known manner by producing an appropriateactuator control signal on signal path 150 ₃. The control valve 1494 iselectrically connected to another actuator output of the PLC circuit 140via signal path 150 ₂, and the PLC circuit 140 is configured to controloperation of the control valve by producing an appropriate actuatorcontrol signal on signal path 150 ₂. The precipitation catalyst solutiontank 1490 is mechanically coupled to a conventional motor 1502, which iselectrically connected to a conventional motor driver 1504. The motordriver 1504 is electrically connected to another actuator output of thePLC circuit 140 via signal path 150 ₄. The PLC circuit 140 is configuredto control the operation of the motor 1502 by producing an appropriateactuator control signal on signal path 150 ₄.

The precipitation catalyst solution tank 1490 is filled with aprecipitation catalyst solution, and the PLC circuit 140 is configuredto periodically activate the motor 1502 for a predefined time period tomix the precipitation catalyst solution within the tank 1490. In theillustrated embodiment, the PLC circuit 140 is further configured tomaintain the control valve 1494 open and to control the speed of thepump 1496 to supply the precipitation catalyst solution to the inlet ofthe inlet diverter valve 1480 at a target precipitation catalystsolution flow rate. The precipitation catalyst solution thus mixes withthe residual liquid supplied to the inlet of the inlet diverter valve1480 via conduit 74, and this mixture is then supplied to theprecipitation tanks 1484 and 1488 in alternating fashion via control ofthe inlet diverter valve. The precipitation catalyst solution isselected to modify the residual liquid supplied via conduit 74 in amanner that will facilitate precipitation of residual waste out of theresidual liquid within the precipitation tanks 1484 and 1488. Forexample, residual liquids resulting from fermentation of biomaterialwaste, such as animal waste, may have residual phosphorus-basedcomponents or nutrients. Suitable precipitation catalyst solutions mayinclude, but are not limited to, clay, ferric-clay, limestone, ferriclimestone, calcium carbonate, calcium carbonate-iron complexes,vermiculites, silica, aluminum silicates, bentonites, and the like, andcombinations thereof.

The first precipitation tank 1484 further includes a pH adjustmentsolution inlet fluidly coupled to an outlet of a control valve 1512 viaan inlet conduit 1510. The second precipitation tank 1488 also includesa pH adjustment solution inlet fluidly coupled to an outlet of anothercontrol valve 1518 via an inlet conduit 1516. The control valve 1512 iselectrically connected to another actuator output of the PLC circuit 140via signal path 150 ₅, and the control valve 1518 is electricallyconnected to yet another actuator output of the PLC circuit 140 viasignal path 150 ₆. The PLC circuit 140 is operable to control theoperation of each of the control valves 1512 and 1518 by producingappropriate actuator control signals on signal paths 150 ₅ and 150 ₆respectively. The inlets of valves 1512 and 1518 are fluidly coupled toan outlet of a conventional liquid pump 1514 having a pump inlet fluidlyconnected to an outlet of another control valve 1524 via a conduit 1522.The pump 1514 is electrically connected to a conventional pump driver1520 that is also electrically connected to an actuator output of thePLC circuit 140 via signal path 150 ₇. The PLC circuit 140 is configuredto control the speed of the pump 1514 in a known manner by producing anappropriate actuator control signal on signal path 150 ₇.

The outlet of the control valve 1524 is coupled to a fluid outlet of apH adjustment solution tank 1526, and the control valve 1524 iselectrically connected to another actuator output of the PLC circuit 140via signal path 150 ₈. The PLC circuit 140 is configured to controloperation of the control valve 1524 by producing an appropriate signalon signal path 150 ₈. The pH adjustment solution tank 1526 ismechanically coupled to a conventional motor 1528, which is electricallyconnected to a conventional motor driver 1530. The motor driver 1530 iselectrically connected to another actuator output of the PLC circuit 140via signal path 150 ₉. The PLC circuit 140 is configured to control theoperation of the motor 1528 by producing an appropriate actuator controlsignal on signal path 150 ₉.

The pH adjustment solution tank 1526 is filled with a pH adjustmentsolution, and the PLC circuit 140 is configured to periodically activatethe motor 1528 for a predefined time period to mix the pH adjustmentsolution within the tank 1526. In the illustrated embodiment, the PLCcircuit 140 is further configured to maintain the control valve 1524open and to control the speed of the pump 1514 to supply the pHadjustment solution to the inlets of the control valves 1512 and 1518 ata target pH adjustment solution flow rate. The PLC circuit 140 isfurther configured to control operation of the control valves 1512 and1518 to selectively supply the pH adjustment agent to the precipitationtanks 1484 and 1488 in alternating fashion. The pH adjustment solutionis selected to controllably change the pH level of the residual liquidand precipitation catalyst solution mixture in each of the precipitationtanks 1484 and 1488 to thereby precipitate residual waste out of theresidual liquid to produce “cleaned” water that is substantially free ofharmful organic or inorganic chemical substances and that can safely bereleased from the residual liquid processing unit 16 as ground water.For residual liquids resulting from fermentation of biomaterial waste inthe form of animal waste, suitable pH adjustment solutions may include,but are not limited to, lime, calcium carbonate, iron-fortified calciumcarbonate, and the like, and combinations thereof.

The first precipitation tank 1484 further includes a cleaned wateroutlet fluidly coupled to one inlet of an outlet diverter valve 1542 viaa cleaned water outlet conduit 1544, and the second precipitation tank1488 also has a cleaned water outlet fluidly coupled to another inlet ofthe outlet diverter valve 1542 via another cleaned water outlet conduit1540. An outlet of the outlet diverter valve 1542 is fluidly coupledthrough a mechanical on/off valve, Mv, and a butterfly valve, BV, to aninlet of another conventional liquid pump 1548 having a pump outletfluidly coupled through additional mechanical on/off valves, MV, to thefirst and second liquid outlets, LO1 and LO2, of the residual liquidprocessing unit 594, and thus to the liquid outlet conduits 78 and 82respectively. The mechanical valves, MV, at the liquid outlets LO1 andLO2 may be suitably manipulated to direct the flow of liquid from thepump 1548 out of the residual liquid processing unit 16 via conduit 82,or alternatively back to the liquefied waste source 20 via conduit 76.In any case, the outlet diverter valve 1542 is electrically connected toan actuator output of the PLC circuit 140 via signal path 150 ₁₀, andthe PLC circuit 140 is configured to control operation of the outletdiverter valve 1542 by producing an appropriate signal on signal path150 ₁₀. The pump 1548 is electrically connected to a conventional pumpdriver 1550 that is also electrically connected to an actuator output ofthe PLC circuit 140 via signal path 150 ₁₁. The PLC circuit 140 isconfigured to control the speed of the pump 1548 in a known manner byproducing an appropriate actuator control signal on signal path 150 ₁₁.In operation, the PLC circuit 140 is operable to control the position ofthe outlet diverter valve 1542 and the speed of the pump 1548 toselectively remove the cleaned water from the precipitation tanks 1484and 1488 in alternating fashion.

The first precipitation tank 1484 further includes a precipitated wasteoutlet fluidly coupled to an inlet of a control valve 1572 via a conduit1570. The second precipitation tank 1488 also includes a precipitatedwaste outlet fluidly coupled to an inlet of another control valve 1562via a conduit 1560. The control valve 1562 is electrically connected toanother actuator output of the PLC circuit 140 via signal path 150 ₁₂,and the control valve 1572 is electrically connected to yet anotheractuator output of the PLC circuit 140 via signal path 150 ₁₃. The PLCcircuit 140 is operable to control the operation of each of the controlvalves 1562 and 1572 by producing appropriate actuator control signalson signal paths 150 ₁₁ and 150 ₁₂ respectively. The outlets of thecontrol valves 1562 and 1572 are fluidly coupled to an inlet of anotherconventional pump 1564 via a conduit 1568, and an outlet of the pump1564 is fluidly coupled to the precipitated waste outlet, PWO, of theresidual liquid processing unit 16 and also to the precipitated wasteoutlet conduit 80. The pump 1564 is electrically connected to aconventional pump driver 1574 that is also electrically connected to anactuator output of the PLC circuit 140 via signal path 150 ₁₄ and alsoto a sensor input of the PLC circuit 140 via signal path 144 ₃. The PLCcircuit 140 is configured to control the speed of the pump 1564 in aknown manner by producing an appropriate actuator control signal onsignal path 150 ₁₄. The pump driver 1574 is responsive to an actuatorcontrol signal supplied by the PLC 140 on signal path 150 ₁₄ to drivethe pump 1564, and the pump driver 1574 and/or pump 1564 furtherincludes a “sensor” for determining and monitoring the operating torqueof the pump 1564. Such a “sensor” may be a conventional strain-gaugetype torque sensor operatively coupled to a rotating drive shaft of thepump 1564 and operable to produce a sensor signal corresponding to theoperating torque of the pump 1564, or may alternatively be a so-calledvirtual sensor implemented in the form of one or more softwarealgorithms resident within the PLC circuit 140 and responsive to one ormore measurable operating parameters associated with the pump driver1574 and/or pump 1564 to derive or infer the operating torque value. Forexample, the pump driver 1574 may include a current sensor producing acurrent sensor signal indicative of drive current being drawn by thepump driver 1574, and/or the pump 1564 may include a position and/orspeed sensor producing a signal corresponding to the rotational speedand/or position of the pump 1564. The PLC circuit 140 may be responsiveto any such sensor signals, and/or to other information relating to theoperation of the pump driver 1574 and/or pump 1564, to estimate theoperating torque of the pump 1564 as a known function thereof. In anycase, the signal path 144 ₃ carries one or more torque feedback signalsto the PLC circuit 140 from which the operating torque of the pump 1564may be determined directly or estimated. In operation, the PLC circuit140 is operable to control operation of the control valves 1562 and 1572and the speed of the pump 1564 to selectively remove precipitated wastefrom the precipitation tanks 1484 and 1488 in alternating fashion.

The residual liquid processing unit 16 is operable, under control of thePLC circuit 140, to fill one of the precipitation tanks 1484, 1488 withthe residual liquid and precipitation catalyst solution mixture whilethe other tank 1484, 1488 is emptied of water. As either of theprecipitation tanks 1484, 1488 is being filled, the pH adjustmentsolution is added to controllably change the pH level of the mixture andcause excess waste in the residual liquid to precipitate out. The timingof the inlet diverter valve 1480 and the outlet diverter valve 1542, andof the control valves 1512 and 1518, as well as the speed of the liquidoutlet pump 1548, are controlled by the PLC circuit 140 so that whileone of the precipitation tanks 1484, 1488 is being filled, the othertank 1484, 1488 is being emptied. Removal of the precipitated waste needonly occur occasionally; e.g., every several days or weeks, andoperation of the control valves 1562 and 1572 and of the solids outletpump 1564 may therefore be independent and asynchronous with theremaining components of the residual liquid processing unit 16.

Referring now to FIG. 30, a flowchart of one illustrative embodiment ofa software control algorithm 1600 for controlling the residual liquidprocessing unit 16 of FIG. 29 is shown. It will be understood that thesoftware algorithm 1600 represents one illustrative strategy forcontrolling the residual liquid processing unit 16 during normal,continuous flow operation of the biomaterial waste processing system 10,and that the residual liquid processing unit 16 may be controlleddifferently during other operational modes of the biomaterial wasteprocessing system 10. The software algorithm 1600 includes a number ofdifferent and independently executing control routines, and each ofthese different control routines will be described separately. Forexample, the control algorithm 1600 includes a first control routine1602 for controlling the filling and emptying of the precipitation tanks1484 and 1488. The control routine 1602 begins at step 1604 where thePLC circuit 140 is operable to control the precipitation catalyst pump1496 to a target pump speed, S1. In the illustrated embodiment, thetarget pump speed, S1, is selected to provide a target flow rate of theprecipitation catalyst solution from the precipitation catalyst solutiontank 1490 to the inlet of the inlet diverter valve 1480, wherein thistarget flow rate is dependent on a number of factors including, but notlimited to, the flow rate and flow volume of the residual liquidsupplied to the inlet of the inlet diverter valve 1480, the desiredratio of residual liquid and precipitation catalyst solution, thechemical make up of the precipitation catalyst solution, and the like.In any case, for normal, continuous flow operation of the biomaterialwaste processing system 10, the residual liquid flows into the residualliquid inlet, RLI, of the residual liquid processing unit 16 at asubstantially constant rate, and the target speed, S1, of theprecipitation catalyst pump 1496 will accordingly be a substantiallyconstant pump speed.

Following step 1604, the PLC circuit 140 is operable at step 1606 tocontrol the inlet diverter valve 1480 to fill one of the precipitationtanks 1484, 1488 with the residual liquid and precipitation catalystsolution mixture while the other precipitation tank 1484, 1488 is beingemptied. In the illustrated embodiment, the PLC circuit 140 isconfigured to execute step 1606 by controlling the inlet diverter valve1480, via an appropriate actuator control signal on signal path 150 ₁,to fluidly couple the inlet of the inlet diverter valve 1480 to conduit1482 to fill the first precipitation tank 1484 with the residual liquidand precipitation catalyst solution mixture, or to fluidly couple theinlet of the inlet diverter valve 1480 to conduit 1486 to fill thesecond precipitation tank 1488 with the residual liquid andprecipitation catalyst solution mixture. Thereafter at step 1608, thePLC circuit 140 is operable to control the pH adjustment solution pump1514 to a target pump speed, S2, and to control the pH adjustmentsolution inlet valves 1512 and 1518 to introduce the pH adjustmentsolution to the precipitation tank 1484, 1488 being filled. In oneillustrative embodiment, as described hereinabove, the PLC circuit 140is operable to continuously control the pH adjustment solution pump 1514to the target pump speed, S2, wherein the target pump speed, S2, isselected to provide a continuous target flow rate of the pH adjustmentsolution from the pH adjustment solution tank 1526 to the pH adjustmentsolution inlet valves 1512 and 1518. In this embodiment, the PLC circuit140 is operable to execute step 1608 by controlling the flow of the pHadjustment solution to the precipitation tanks 1484, 1488 via control ofthe inlet valves 1512 and 1518 in alternating fashion. Alternatively,the PLC circuit 140 may be configured to execute step 1608 bysimultaneously opening an appropriate one of the inlet valves 1512, 1518while closing the other inlet valve 1512, 1518 and activating the pHadjustment solution pump 1514 at the target pump speed, S2, andotherwise maintaining the inlet valves 1512 and 1518 closed anddeactivating the pump 1514. In either case, the target pump speed, S2,is selected to provide a target flow rate of the pH adjustment solutionfrom the pH adjustment tank 1526 to the pH adjustment solution inlet ofthe precipitation tanks 1484, 1488, wherein this target flow rate isdependent on a number of factors including, but not limited to, themixture fill rate and fill volume of the precipitation tanks 1484, 1488,the timing, relative to the process of filling the precipitation tanks1484, 1488 with the residual liquid and precipitation catalyst mixture,that the pH adjustment solution is added to the precipitation tanks1484, 1488, the desired ratio of residual liquid and pH adjustmentsolution, the chemical make up of the pH adjustment solution, and thelike.

Following step 1608, the PLC circuit 140 is operable at step 1610 todetermine the level, L1, of the fluid in the precipitation tank 1484,1488 being filled. In the illustrated embodiment, the PLC circuit 140 isconfigured to execute step 1610 by monitoring the signal produced by anappropriate one of the pressure sensors 142 ₁, 142 ₂ on a correspondingsignal path 144 ₁, 144 ₂, and processing the pressure signal in a knownmanner to determine L1. It will be understood, however, that the PLCcircuit 140 may be alternatively configured to determine the liquidlevel, L1, in accordance with any one or more other known liquid leveldetermining techniques using any one or more other known sensors fromwhich L1 may be determined directly or indirectly. In any case,execution of the control routine 1602 advances from step 1610 to step1612 where the PLC circuit 140 is operable to compare L1 to a thresholdlevel value, L1 _(TH), where L1 _(TH) represents a level at which theprecipitation tanks 1484, 1488 are considered to be full. If, at step1612, L1 is less than L1 _(TH), execution of the control routine 1602loops back to step 1610 to continue to determine and monitor L1. If,however, L1 is greater than or equal to L1 _(TH) at step 1612, executionof the control routine 1602 advances to step 1614 where the PLC circuit140 is operable to control the outlet diverter valve 1542, and operatethe outlet pump 1548 at a target speed, S3, to begin emptying cleanedwater from the now filled precipitation tank 1484, 1488.

In the illustrated embodiment, the PLC circuit 140 is operable tocontinuously control the outlet pump 1548 to the target pump speed, S3,wherein the target pump speed, S3, is selected to remove the cleanedwater from the precipitation tanks 1484, 1488 at a continuous targetflow rate. In this embodiment, the PLC circuit 140 is operable toexecute step 1614 by controlling the outlet diverter valve 1542, inalternating fashion, to one position fluidly coupling the cleaned wateroutlet conduit 1544 to the outlet of the diverter valve 1542 to therebyremove cleaned water from the first precipitation tank 1484, or bycontrolling the outlet diverter valve 1542 to an opposite positioncoupling the cleaned water outlet conduit 1540 to the outlet of thediverter valve 1542 to thereby remove cleaned water from the secondprecipitation tank 1488. In either case, the target pump speed, S3, isselected to remove cleaned water from the precipitation tanks 1484, 1488at a target flow rate, wherein the target flow rate is dependent on anumber of factors including, but not limited to, the mixture fill rateand fill volume of the precipitation tanks 1484, 1488, the timing,relative to the process of filling the precipitation tanks 1484, 1488with the residual liquid and precipitation catalyst mixture, that the pHadjustment solution is added to the precipitation tanks 1484, 1488, therate of nutrient precipitation in the precipitation tanks 1484, 1488,and the like. Execution of the control routine 1602 loops from step 1614back to step 1606.

Step 1606 of the control routine 1602 also advances to step 1616 wherethe PLC circuit 140 is operable to determine the level, L2, of the fluidin the precipitation tank 1484, 1488 being emptied. In the illustratedembodiment, the PLC circuit 140 is configured to execute step 1616 bymonitoring the signal produced by an appropriate one of the pressuresensors 142 ₁, 142 ₂ on a corresponding signal path 144 ₁, 144 ₂, andprocessing the pressure signal in a known manner to determine L2. Itwill be understood, however, that the PLC circuit 140 may bealternatively configured to determine the liquid level, L2, inaccordance with any one or more other known liquid level determiningtechniques using any one or more other known sensors from which L2 maybe determined directly or indirectly. In any case, execution of thecontrol routine 1602 advances from step 1616 to step 1618 where the PLCcircuit 140 is operable to compare L2 to a threshold level value, L2_(TH), where L2 _(TH) represents a level at which the precipitationtanks 1484, 1488 are considered to be emptied of cleaned water. If, atstep 1618, L1 is greater than L2 _(TH), execution of the control routine1602 loops back to step 1616 to continue to determine and monitor L2.If, however, L2 is less than or equal to L2 _(TH) at step 1618,execution of the control routine 1602 advances to step 1620 where thePLC circuit 140 is operable to control the outlet diverter valve 1542 tobegin removing cleaned water from the opposite precipitation tank 1484,1488. Execution of the control routine 1602 loops from step 1620 back tostep 1606.

For normal, continuous flow operation of the residual liquid processingunit 16, control routine 1602 is coordinated in the timing of itsvarious execution branches so that one precipitation tank 1484, 1488 isbeing filled with the residual liquid and precipitating catalystsolution mixture while the other precipitation tank 1484, 1488 is beingsimultaneously emptied of cleaned water. In such a continuous flowsystem, steps 1614 and 1620 thus loop directly back to step 1606 ofcontrol routine 1602. For non-continuous flow operation, control routine1602 may require one or more delay steps to coordinate the filling ofone precipitation tank 1484, 1488 with the emptying of the otherprecipitation tank 1484, 1488.

In any case, the residual liquid processing unit control algorithm 1600includes another control routine 1622 that operates independently ofcontrol routine 1602 so that precipitated waste may be periodicallyextracted from the precipitation tanks 1484, 1488 independently from theliquid filling and emptying operations. Control routine 1622 begins atstep 1624 where the PLC circuit 140 is operable to periodically controlthe precipitated waste outlet valves 1562 and 1572 and activate theprecipitated waste extraction pump 1564 to extract precipitated wastefrom each of the precipitation tanks 1484, 1488. The PLC circuit 140 maybe operable to control the precipitated waste outlet valves 1562 and1572 to extract precipitated waste from both of the precipitation tanks1484 and 1488 simultaneously, or may alternatively control theprecipitated waste outlet valves 1562 and 1572 to extract precipitatedwaste from only one of the precipitation tanks 1484, 1488 at a time. Ineither case, execution of the control routine 1622 advances from step1624 to step 1626 where the PLC circuit 140 is operable to determine theoperating torque, TQ, of the precipitated waste extraction pump 1564. Inthe illustrated embodiment, the PLC circuit 140 is operable to executestep 1626 using any of the feedback torque monitoring techniquesdescribed hereinabove.

Following step 1626, the PLC circuit 140 is operable at step 1628 tocompare the operating torque, TQ, of the precipitated waste extractionpump 1564 to a torque threshold, TQ_(TH). As precipitated waste isextracted from either, or both, of the precipitation tanks 1484, 1488,the operating torque of the pump 1564 will decrease due to thediminishing quantity of the precipitated waste in either, or both, ofthe precipitation tanks 1484, 1488. The torque threshold TQ_(TH)corresponds to an operating torque of the pump 1564 below which either,or both, of the precipitation tanks 1484, 1488 may be considered to besufficiently emptied of precipitated waste. Thus, if the PLC circuit 140determines at step 1628 that TQ is greater than or equal to TQ_(TH),either, or both, of the precipitation tanks 1484, 1488 still hold aquantity of precipitated waste that may be removed, and execution of thecontrol routine 1622 thus loops back to step 1626. If, however, the PLCcircuit 140 determines at step 1628 that TQ is less than TQ_(TH),sufficient precipitated waste has been extracted from either, or both,of the precipitation tanks 1484, 1488 to consider it/them emptied ofprecipitated waste, and execution of the control routine 1622 advancesto step 1630 where the PLC circuit 140 is operable to deactivate theprecipitated waste extraction pump 1564 and close either, or both, ofthe outlet valves 1562, 1572. From step 1630, execution of the controlalgorithm 1622 loops back to step 1624.

Further details relating to the interaction between the residual liquidsupplied to the residual liquid inlet, RLI, of the residual liquidprocessing unit 16 and the precipitation catalyst solution, as well asthe interaction between the residual liquid and precipitation catalystsolution mixture and the pH adjustment solution, are disclosed inPCT/US2005/______, entitled SYSTEM FOR REMOVING SOLIDS FROM AQUEOUSSOLUTIONS (attorney docket no. 35479-77847) which is assigned to theassignee of the present invention and is incorporated herein byreference.

It will be understood that while many of the actuator driversillustrated the drawings have been described as being controlledrelative to maximum or minimum output torque values, at least some ofsuch actuator drivers, particularly those driving some augers and pumps,may be conventional variable frequency drivers (VFD) capable ofoperating, at least for brief periods, at output torque values wellabove their rated maximum output torque values. When high startingtorque or intermittent high torque loads are expected, e.g., as may bethe case with one or more of the sand augers illustrated and describedherein, such VFD's may be operated well above their rated maximum outputtorque values, e.g., 180% of the rated maximum, for brief time periods,e.g., 1-3 seconds, in order to “break” inertia or to overcome a highstart-up load.

While the invention has been illustrated and described in detail in theforegoing drawings and description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly illustrative embodiments thereof have been shown and described andthat all changes and modifications that come within the spirit of theinvention are desired to be protected. For example, the various softwarealgorithms and control structures described herein are provided toillustrate example operation of the biomaterial waste processing system10 in a normal, continuous flow operating mode with the biomaterialwaste being comprised of livestock waste. It will be appreciated thatthe biomaterial waste processing system 10 may include additional oralternative control algorithms when operating in modes other thannormal, continuous flow operation and/or with biomaterial wastecomprised of biomaterial waste other than livestock waste. In any case,such other software algorithms and control structures are intended tofall within the scope of the claims appended hereto.

Illustrative Embodiments of a Process and Apparatus for Treatment of aBiomaterial Waste Stream

Illustrative biomaterial waste streams that can be treated with thetreatment processes described herein include, but are not limited to,manure, cellulosistic solid waste, feathers, hair, whey broth fromcheese production or biomaterial waste streams from other foodstuffs,broth remediation from alcohol or yeast production, tannery waste,slaughterhouse waste, tallow waste from rendering processes andincluding waste fats and oils, waste derived from plants, paperprocessing waste, land fill waste, and the like. The waste derived fromplants can be, for example, waste from hay, leaves, weeds, sawdust, orwood and can be, for example, yard waste, landscaping waste,agricultural crop waste, forest waste, pasture waste, or grasslandwaste. The waste derived from foodstuffs can be fruit and vegetableprocessing waste, fish and meat processing wastes, bakery product waste,cheese whey, and the like. In embodiments where the waste is manure, themanure can be from an animal such as a human, a bovine animal, an equineanimal, an ovine animal, a porcine animal, or poultry. In general, anyorganic waste containing proteins, simple carbohydrates, complexcarbohydrates, lipids, and combinations thereof, can be pretreated asdescribed herein.

In one embodiment, the processes described herein may be used for a widevariety of biomaterial waste streams for removing pollutants from thebiomaterial waste stream, and alternatively converting the pollutants toa valuable product by fermentation. The treated biomaterial waste streammay be further processed using any number of additional apparatus orprocesses including those used to process biomaterial waste streams byfermentation, such as the systems, processes, and apparatus describedherein and in PCT applications serial. nos. PCT/US2005/______, entitledSYSTEM FOR PROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no.35479-77858), PCT/US2005/______, entitled FERMENTER AND FERMENTATIONMETHOD (attorney docket no. 35479-77851), PCT/US2005 entitledFLOCCULATION METHOD AND FLOCCULATED ORGANISM (attorney docket no.35479-77852), PCT/US2005/______, entitled SYSTEM FOR REMOVING SOLIDSFROM AQUEOUS SOLUTIONS (attorney docket no. 35479-77847) incorporatedherein by reference. Further, the biomaterial waste stream may bedirectly derived from the source producing the waste, or may be theproduct of another process, method, system, or apparatus for treatingbiomaterial waste streams directly derived from the source producing thewaste, including but not limited to the methods, processes, andapparatus described in PCT/US2005/______, entitled SAND AND ANIMAL WASTESEPARATION SYSTEM (attorney docket no. 35479-77857) incorporated hereinby reference.

In one embodiment, the biomaterial waste stream is a variable and dilutebiomaterial waste stream derived from animal manure including waste frombarn animals ruminants and partial ruminants, such as beef cattle, dairycattle, and horses, and/or from swine, poultry, and the like.

In one embodiment, the treatment processes and apparatus describedherein include a separating step. The separating step may be based onseparating components having differing sizes, densities, or otherdistinguishing properties. In an embodiment where the biomaterial wastestream is derived from animal manure, the biomaterial waste stream caninclude higher density components such as sand, dirt, gravel, and thelike, and combinations thereof; and lower density components such asfiber, hay, straw, bedding straw, sawdust, other cellulosistic material,hair, completely and incompletely digested feed, including protein andprotein digestion residues, whole grain, spilled feed, and the like, andcombinations thereof. Alternatively, these same components found inbiomaterial waste streams derived from animal manure may be separatedfrom each other according to relative size. In any case, separation ofone component class from the other is contemplated in the processes andapparatus described herein. In one aspect, where the separation ofcomponents in the biomaterial waste stream is a density-basedseparation, the lower density components may have a high level ofcellulose, hemicellulose, and cellulose-related components. The higherdensity material may be separated from the lower density material, andeach separated from the liquefied waste; or the small particles may beseparated from the large particles, and each separated from theliquefied waste; by any conventional solid/liquid separation process, orby introducing the biomaterial waste stream into the solid/liquidseparation unit described herein and in PCT/US2005/______, entitledSYSTEM FOR PROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no.35479-77858).

In variations of the processes and apparatus described herein, thebiomaterial waste stream from barn animals includes dissolved andundissolved components that may be precipitated by admixing withaggregation agents or catalysts, binding agents, and the like, by heattreatment, by adjusting the pH, and similar processes, and combinationsthereof. Once precipitated, these additional components may be separatedin a solid/liquid separation unit as described above.

In one aspect, biomaterial waste streams from barn animals includemanure from full ruminants such as mature cattle, beef cattle, and dairycattle. In another aspect, biomaterial waste streams from barn animalsinclude manure from semi-ruminants or partial ruminants, such as horses.It is appreciated that biomaterial waste streams from semi-ruminants mayinclude more or substantially more cellulose fiber, and/or less orsubstantially less completely digested material than biomaterial wastestreams from full ruminants. It is also appreciated that the treatmentof biomaterial waste streams from semi-ruminants, using the processesand apparatus described herein, may include more vigorous or harsherconditions than included in comparable treatment of biomaterial wastestreams from full ruminants. Harsher and/or more vigorous conditionsinclude higher temperatures, more extreme pH levels such as more acidicor more basic pH levels, higher acid concentrations, higher baseconcentrations, more aggressive enzymes, less selective enzymes, enzymeswith higher turnover rates, more aggressive microorganism, and the like.

In another aspect of biomaterial waste streams derived from ruminant andpartial or semi-ruminant animals, the waste stream may have a relativelyhigh proportion of lignin. It is understood that ruminant and semiruminant animals more efficiently remove useful nutrients, such ascarbohydrates, from the fiber component of their feed than do otheranimals, such as swine and poultry. Therefore, it is appreciated thatthe lignin fraction is effectively concentrated and forms a relativelyhigher proportion in the waste from ruminant and semi-ruminant animals.

In another embodiment, the biomaterial waste stream is derived fromanimal manure, such as manure from swine, and includes higher densitycomponents such as sand, dirt, gravel, and the like, and combinationsthereof; and lower density components such as fiber, hay, straw, beddingstraw, sawdust, celluloses, hemicelluloses, cellulose relatedcomponents, other cellulosistic material, incompletely digested feedsuch as grain residues, corn meal, soy meal, and the like, whole grain,spilled grain, hair, proteins, bile acids, starches, starch granules,and the like, and combinations thereof. In variations, the components inthe biomaterial waste stream are distinguished and separated by particlesize rather than density. It is appreciated that this biomaterial wastestream may be directly obtained from the animal, or may be the productof other processes and apparatus as described herein. In addition,dissolved and undissolved components including proteins, bile acids,starches, starch granules, and the like, may be precipitated oraggregated to increase the amount of lower density material. The lowerdensity material, or certain sized components may be separated fromother components as described herein.

In variations of the processes and apparatus described herein, thebiomaterial waste stream from swine includes dissolved and undissolvedcomponents that may be precipitated by admixing with aggregation agentsor catalysts, binding agents, and the like, by heat treatment, byadjusting the pH, and similar processes, and combinations thereof. Onceprecipitated, these additional components may be separated in asolid/liquid separation unit as described above. Such additionalcomponents include proteins, organic acids, bile acids, complexstarches, and cellulose-related molecules, including cellulose andhemicellulose.

In one aspect of biomaterial waste streams from swine, undigested orincompletely digested grain, soy and/or corn meal, and complex starchesmay each be present. It is appreciated that a high proportion of thephosphorus in many grains is in the form complex organic molecules, suchas phytic acid and other phosphoinositols, and is not well-digested,especially by nonruminants including swine. It is further appreciatedthat inorganic phosphate may be recovered from such complex organicmolecules by full or partial hydrolysis, generally at low pH, and/or byhydrolysis using enzymes including phytases.

In one aspect of treating biomaterial waste streams from swine, thetreated waste is used as a liquid waste stream for a fermentationprocess, such as the fermentation processes described herein. It isunderstood that such a treated waste includes nutrients that are used bythe fermenting organism. It is appreciated that the treatment stepsdescribed herein may be performed in a manner that maximizes theproduction of nutrients usable by the fermenting organism. Therefore, insome aspects, the pH of biomaterial waste stream from swine is adjustedto lower levels. Without being bound by theory, it is believed that suchlower pH levels not only facilitate many of the treatment processesdescribed herein, but also stabilize nutrients already present and thoseproduced in the swine waste stream.

In another embodiment, the biomaterial waste stream is derived fromanimal manure, including manure from poultry, such as chickens, ducks,turkeys, and the like, and includes higher density components such assand, dirt, gravel, and the like, and combinations thereof; and lowerdensity components such as feathers, fiber, hay, straw, bedding straw,sawdust, other cellulosistic material, and the like, and combinationsthereof. In variations, the components in the biomaterial waste streamare distinguished and separated by particle size rather than density. Itis appreciated that this biomaterial waste stream may be directlyobtained from the animal, or may be the product of other processes andapparatus as described herein. The lower density material, or certainsized components may be separated from other components as describedherein.

In variations of the processes and apparatus described herein, thebiomaterial waste stream from poultry includes dissolved and undissolvedcomponents that may be precipitated by admixing with aggregation agentsor catalysts, binding agents, and the like, by heat treatment, byadjusting the pH, and similar processes, and combinations thereof. Onceprecipitated, these additional components may be separated in asolid/liquid separation unit as described above. Illustrativeaggregation or precipitation catalysts for protein components includessulfate salts such as sodium sulfate, ammonium sulfate, calcium salts,iron-calcium complexes, transition metals, metal complexes, and thelike.

In one aspect of biomaterial waste streams from poultry, undigested orincompletely digested grain, corn meal and/or soy meal, and othercomplex starches may each be present. In addition, it is appreciatedthat a high proportion of the phosphorus in many grains is in the formof complex organic molecules, such as phytic acid, and these complexorganic molecules are not always well-digested by poultry. It is furtherappreciated that inorganic phosphate may be recovered from such complexorganic phosphate molecules by full or partial hydrolysis, generally atlow pH, and/or by hydrolysis using enzymes including phytases.

In embodiments of the processes and apparatus described herein thatinclude fermentation, it is appreciated that many of the components inthe animal waste are nutrients used by the fermenting organism,including urine, such as ammonia, amines, urea, indole, and othernitrogen compounds, phosphates and other salts, amino acids, and otherorganic acids, including acetic, butyric, valeric, and other acids.

It is appreciated that a solid component containing one or morefiber-like materials may be difficult to process in conventionalfermentation systems until the solid component is treated, such as bysolubization and/or degradation to smaller molecular weight, or morewater soluble components. It is also appreciated that a solid componentcontaining certain proteins, peptides, organic acids, organicphosphates, organic amines, and complex starches may be difficult toprocess in conventional fermentation systems until the solid componentis treated, such as by solubization and/or degradation to smallermolecular weight, or more water soluble components. Pretreatment of thesolid component in a chemical process, enzymatic process, or microbialprocess may convert portions of the component into a product that may berecombined with the liquefied waste prior to additional processing,including sterilization, fermentation, and the like.

In one aspect, prior to chemical, enzymatic, or microbial processing,the solid component is a lower density component including fiber-likematerials. The fiber-like component may be dried, squeezed, drained,filtered, pressed, centrifuged, evaporated, and the like, and/orprocessed in a like manner to remove water. It is appreciated thatremoving water from the fiber-like component may decrease the quantitiesof chemicals, enzymes, and/or microorganisms needed for treatment orprocessing. It is also understood that removal of too much water fromthe fiber-like component may adversely affect mechanical processing,such as decreased ability to stir, and the like. In one aspect, theratio of water to solids is in the range from about 2 to about 10, andis illustratively about 6. In another aspect, the ratio of water tosolids is about 2.

In another aspect, the lower density component includes fiber, hay,straw, bedding straw, sawdust, other cellulosistic material, and thelike, and combinations thereof. It is appreciated that the lower densitycomponent containing fiber-like material may represent as much as about50% of the total solid content (dissolved and undissolved) present inthe biomaterial waste stream. Illustratively, the fiber-like materialrepresents about one-third of the total solid content. In anotheraspect, the lower density component includes feathers and/or hair. Inanother aspect, the lower density component includes proteins,polypeptides, peptides, organic acids, organic phosphates, organicamines, and the like, and combinations thereof that may be precipitatedor otherwise aggregated.

In another aspect, prior to chemical, enzymatic, and/or microbialprocessing, the solid component includes proteins, peptides, organicacids, organic phosphates, organic amines, and complex starches, thatmay be optionally precipitated. The solid component may be in the formof a paste or sludge that is resuspended to form a liquid waste slurrysuitable for chemical, enzymatic, or microbial processing. The liquidwaste slurry illustratively has a solids content in the range from about1% to about 10%, and is illustratively 4%, relative to moisture and anash-free weight determination.

In one embodiment, chemical processing of the solid component containingfiber-like material, feathers, or precipitated material may be performedby treating the component with an acid including, but not limited to,inorganic or mineral acids such as hydrochloric acid, hydrobromic acid,sulfuric acid, and acidic salts thereof, phosphoric acid, and acidicsalts thereof, and the like; and organic acids such as carbonic acid,formic acid, acetic acid, and the like; and combinations thereof. Acidsmay be used at high acidic pH or at low acidic pH, and at highconcentration, and at low concentration. Illustrative pH levels includethose in the range from about −1 to about 4, and in the range from about0 to about 2. Illustrative concentrations include those in the rangefrom about 0.01 M to about 5 M, and 0.1 M to about 1 M. In one aspect,concentrated sulfuric acid is added to the solid component, includingsulfuric acid concentrations in the range from about 70% to about 95%.In another aspect, 78% or 72% sulfuric acid is added to the solidcomponent. In another aspect, dilute sulfuric acid in the range fromabout 1% to about 10%, and illustratively 3% is added to the solidcomponent.

In another embodiment, chemical processing of the solid componentcontaining fiber-like material, feathers, or precipitated material maybe performed by treating the component in a two-stage process, where thefirst stage includes treating the component with a high concentration ofacid, such as a concentration in the range from about 60% to about 90%,and subsequently treating the component with a low concentration ofacid, such as a concentration in the range from about 1% to about 30%.In the first stage, solubilization of the fiber-like material, feathers,or precipitated material may occur. It is appreciated that hydrolysis ofthe fiber-like material, feathers, or precipitated material may alsooccur. In the second stage, hydrolysis of the fiber-like material,feathers, or precipitated material may occur. It is understood thattwo-stage chemical processing of the solid component may be moreefficient because the initial solubilization phase may facilitate thesubsequent or concurrent hydrolysis phase. It is also understood thatsuch a two-stage process may consume less acid overall, than theequivalent single-stage process to achieve the same level ofsolubilization and/or degradation of the fiber-like material, feathers,or precipitated material. It is also understood that such a two-stageprocess may decrease the number of unwanted side reactions, or theamount of unwanted side products formed during either solubilization orhydrolysis, such as decreasing the amount of either formic acid,levulinic acid, furfural, furfuryl alcohol, and the like that isproduced. It is appreciated that in embodiments of the treatmentprocesses and apparatus described herein that include a fermentation,such unwanted side reaction products may inhibit the growth or health ofthe fermenting organism.

In one aspect of chemical processing of the solid component, thesolubilization and/or the hydrolysis step is conducted in a depletedoxygen or substantially oxygen-free environment. Oxygen can be removedfrom the solid components and/or liquid components alike. Oxygen may beremoved by sparging the solid and/or liquid component with another gascapable of displacing or replacing the oxygen that is contained in ordissolved in the solid and/or liquid component. Illustrative gasesinclude nitrogen, carbon dioxide, argon, helium, and the like. It isappreciated that the source of acid, water, acid solution, and the likeused in the solubilization and/or the hydrolysis steps may also bedepleted of or be substantially free of oxygen.

In one embodiment, enzymatic processing of the solid componentcontaining fiber-like material, complex starches, feathers, orprecipitated material may be accomplished by treating the component withone or more enzymes including, but not limited to, one or morecellulases, such as endocellulases, terminal cellulases, and the like,alpha amylase, beta amylase, gamma amylase, a proteolytic enzyme, apeptidase, a protease, a phytase, and the like, and combinationsthereof. In variations of the processes described herein, one or moreenzymes are used in succession, or a mixture of enzymes is usedcontemporaneously. It is appreciated that the conditions for the optimalconversion of the solid component containing waste stream may beadjusted to optimum levels for the enzyme or mixture of enzymes used,including optimum pH ranges, optimum temperatures, and the like. Inaspects where a succession of enzymes or mixtures is used, conditionsfor optimal enzyme conversion for each enzyme may be included in theprocesses described. In aspects where a mixture of enzymes is used, theconditions may be optimized for the collection of enzymes in aggregate,or the conditions may be adjusted in a series of steps, such as for amulti-step enzymatic dwell, where optimum conditions are maintained fora predetermined period of time for a particular enzyme or mixture ofenzymes, followed by changing the conditions to an optimum or optima foranother enzyme or mixture of enzymes. In one aspect of the enzymaticprocesses described herein, the series of steps are similar to thoseused in the brewing industry, where for example, pH and temperature arestepped through a series of optimal levels to accommodate a series ofenzymatic steps or processes. Sources of mixtures of enzymes includesprouted barley, malted barley, malted barley extract, sorghum extract,and the like. Such mixtures are understood to include phytases,cellulases, hemicellulases, amylases, and other enzymes capable ofsubstantially or totally degrading fiber-like material to smallmolecular weight components, or solubilizing fiber-like material, to amaterial useable by fermenting organisms.

It is understood that many such sources of mixtures of enzymes may alsoinclude additional carbohydrate, such as complex starches from thebarley, sorghum, and the like, as well as fiber-based components such asseed husks, and the like. In aspects of the treatment processes andapparatus described herein that form part of a fermentation system, suchas the fermentation systems described herein, this additionalcarbohydrate may be used as a carbon or carbohydrate source by thefermenting organism. In aspects of the treatment processes and apparatusdescribed herein that include a microbial process, for example in thedegradation of proteins, cellulose, and the like, this additionalcarbohydrate may be used as a carbon or carbohydrate source by themicrobes.

In one aspect, the mixture of enzymes includes gamma, beta, and alphaamylase, and proteolytic enzymes derived from malted barley, alsoreferred to as sprouted barley, and the pH and the temperature aregraduated to the optima of these enzymes. It is appreciated that thegraduation may occur continuously at a predetermined rate, or may occurin a series of steps, each having a predetermined residence or dwelltime. It is understood that an optimum step may be also included for theproteolytic enzyme in such processes described herein.

It is appreciated that though the addition of sprouted barley, maltedbarley, malted barley extract, sorghum extract, and the like mixtures ofenzymes that are derived from vegetative matter increases the ChemicalOxygen Demand (COD) of the solid component, the fermenting organism willuse the additional COD along with other nutrients such as nitrogen,potassium, and phosphate. In many cases, the limiting nutrient infermentation processes is carbohydrate, and therefore the additional CODallows the fermenting organism to utilize more of the other nutrientsthan would be otherwise possible.

In another embodiment, chemical processing of the solid componentcontaining fiber-like material, feathers, or precipitated material maybe accomplished by treating the component with an inorganic or organicoxidizing agent. In one aspect, the oxidizing agent is added in astoichiometric amount. In another aspect, the oxidizing agent is addedcatalytically along with an additional component capable of regeneratingthe oxidizing agent, such as oxygen gas. In another embodiment,microbial processing of the solid component containing fiber-likematerial, feathers, or precipitated material may be accomplished bytreating the component with a microorganism.

In one aspect, chemical processing, enzymatic processing, microbialprocessing, and combinations thereof are performed for a time sufficientto degrade at least a portion of the fiber-like or precipitated materialinto smaller poly and oligosaccharides, or single sugars, smaller polyor oligopeptides, or single amino acids, and smaller poly phosphates, orinorganic phosphates. Such degradation products may be used by amicroorganism in a fermentation process as a carbohydrate source, anitrogen source, or a phosphorus source for its growth and/orproliferation. In another aspect, chemical processing, enzymaticprocessing, microbial processing, and combinations thereof are performedfor a time sufficient to solubilize at least a portion of the fiber-likeor precipitated material. Such solubilized products may be used by amicroorganism in a fermentation process as a carbohydrate source, anitrogen source, or a phosphorus source for its growth and/orproliferation.

In another aspect, chemical processing, enzymatic processing, microbialprocessing, and combinations thereof are performed at a predeterminedtemperature. Chemical processing involving acids, bases, oxidizingagents, and the like, may be performed at elevated temperatures tofacilitate degradation. Enzymatic processing and/or microbial processingmay be performed at elevated temperatures or temperatures below ambientdepending upon the stability of the enzyme or enzymes, or microorganismor microorganisms used in the process.

In another aspect, the biomaterial waste stream includesphosphorus-containing organic molecules, such as phytic acid(myoinositolhexaphosphate) and/or other phosphoinositols.Illustratively, phytic acid may account for about 50% of thephosphorus-containing substances in the biomaterial waste stream,including inorganic phosphorus compounds. It is appreciated thatbiomaterial waste streams from ruminants and partial ruminants, such asmature dairy and beef cattle and horses, may not contain substantialamounts of phytic acid, or may contain much less phytic acid than otherbiomaterial waste streams, such as waste streams from non ruminantsincluding swine and poultry.

In another embodiment, the treatment processes and apparatus describedherein include combining biomaterial waste streams with one or morephytases, such as phytases from plant and grain sources including maltedor sprouted grain. Phytases may also be obtained from the fermentationof yeast, or other microorganism that is capable of producing phytasescapable of hydrolyzing phytic acid to inorganic phosphate among otherthings.

It is understood that phytic acid and other organic phosphates oftenarise in the waste because the animal feed is supplemented with grains,such as corn and soy meal. It is therefore appreciated that biomaterialwaste streams coming from animals whose feed has been supplemented withother sources of phosphorus, including the yeast products describedherein and in PCT applications serial nos. PCT/US2005/______, entitledSYSTEM FOR PROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no.35479-77858), PCT/US2005/______, entitled FERMENTER AND FERMENTATIONMETHOD (attorney docket no. 35479-77851), and PCT/US2005/______,entitled FLOCCULATION METHOD AND FLOCCULATED ORGANISM (attorney docketno. 35479-77852) may have lower proportions of phytic acid.

In embodiments of the processes and apparatus described herein that willform part of a fermentation system, it is appreciated that as aproportion of total nutrient useable by a fermenting organism, thephosphorus component may be in excess. The fermenting organismsrequirements for carbohydrate, nitrogen, potassium, and other nutrientsmay exceed their relative supply in most animal waste streams. Thus, atthe end of fermentation, there may be excess nutrient as the limitingnutrient is exhausted. In some embodiments, the excess nutrients areinorganic phosphate salts, organophosphates, and other phosphorus-basedcompounds. Additional nutrients may be added to compensate for therelative abundance of phosphorus to assist its overall removal from thewaste stream, and also to maximize the yield of fermenting organismproduced, including, sucrose, corn syrup, molasses, ammonia, and thelike. In addition, the treatment processes and apparatus describedherein are illustrative of ways of increasing the relative amount ofother nutrients, such as carbohydrates derived from fiber-based solidsand amino acids derived from protein-based solids.

In variations of the processes described herein where additionalnutrient is added, when carbohydrate is the limiting nutrient, simplecarbohydrates may be added, such as glucose, sucrose, fructose, cornsyrup, molasses, and the like, and combinations thereof. In variationsof the processes described herein where additional nutrient is added,when nitrogen is the limiting nutrient, nitrogen sources may be addedsuch as ammonia, ammonium hydroxide, ammonium chloride, and the like,and combinations thereof. Addition of these supplemental nutrients maybe take place at any convenient step in the overall process.Illustratively, the supplemental nutrient is added before sterilization,or between sterilization and fermentation. It is appreciated that stepsthat include pH adjustment of the liquid waste stream may occur afterthe addition of some supplements, such as the nitrogen containingnutrients because of the possible pH change brought about by theaddition. It is further understood that when nitrogen containingsupplements are added, the addition illustratively occurs in betweensterilization and fermentation to minimize the production of complicatednitrogen-containing compounds occurring at the high sterilizationtemperatures, such as alkaloids that may adversely affect thefermentation step.

In another aspect, the biomaterial waste stream includes dissolved andundissolved solids such as lignans, lignins, chitin, and othersubstances. In some cases, lignin is present from incomplete ruminantdigestion. Some dissolved and undissolved solids will also survive thetreatment processes described herein, and may be optionally removed fromthe treated biomaterial waste stream. Illustratively, the dissolved andundissolved solids or surviving substances may be removed byconventional methods of removing suspended solids from liquids, such asby filtration or by collecting the fine fiber material on a vibratingscreen.

In waste streams where lignin is present, the lignin may be present witha solid fraction that may be entrained on a shaker screen, such asfiber, bedding, straw, and other cellulosistic waste components.Alternatively, lignin may also be present in the liquid passing throughthe shaker screen. Lignins may also be present in a high density, smallparticle solid fraction that may be separated from a liquid fraction byallowing the solids to settle out of the liquid fraction, or by applyinga force to separate higher density components, such as a centripetal orcentrifugal force. Finally, in other waste streams, such as fromnon-ruminant animals, some lignin may still form part of the celluloseor fiber-based solid material as part of the matrix. It is generallyunderstood that waste coming from ruminant animals will typicallycontain more free lignin than waste coming from non-ruminant, or partialor semi ruminant animals where the lignin may still form part of thecellulose-based matrix.

In embodiments of the processes and apparatus described herein thatinclude fermentation of the treated waste stream, the lignin present inthe liquid fraction may be removed by filtration before entry intofermentation and/or sterilization steps in the process. It isappreciated that precipitation of the lignin in larger aggregateparticles may be facilitated by adjusting the pH or by heating to easefiltration and prevent filter clogging. In general, it is appreciatedthat the lignin removal may be accomplished by conventional techniquessuch as those used in the paper industry and in paper-pulp processing.

Lignin that is collected with the solid fraction in the solid/liquidseparation processes described herein may be illustratively removed withthe apparatus shown in FIG. 45 and with an associated process describedherein. It is understood that certain processes used for treating thesolid fraction may release additional lignin from the cellulose-basedmatrix. This additional lignin fraction released after any of thehydrolysis or mild hydrolysis processes described herein may be removedby filtration. In embodiments that form part of a fermentation process,the filtration may take place before or after the extract isreintroduced into the liquid waste stream, such as before sterilization,or before fermentation. Lignin that is not removed prior to fermentationmay be removed as part of the fermenting organism fraction removed fromfermentation systems, such as by flocculation. It is appreciated thatlignin that is trapped with the fermenting organism during flocculationsteps may be advantageous. In embodiments where the flocculatedfermenting organism is subsequently used as a feed supplement, ligninsmay as act binding agents for ease of handling. Lignin may also beremoved following fermentation using processes and apparatus describedherein for removing dissolved and undissolved solids from aqueoussolutions.

Solids that are separated from liquefied biomaterial waste streams maybe treated by contacting the solid fraction with an acid to solubilizeand/or hydrolyze at least a portion of the solid fraction. In oneembodiment, the solid fraction is subjected to acid solubilization andhydrolysis. Acid solubilization and hydrolysis may be performed with anacid, such as a mineral acid including sulfuric acid, at a relativeconcentration in the range from about 60% to about 90%, illustrativelyin the range from about 70% to about 80%, and illustratively about 72%or at about 78%. Hydrolysis and solubilization may be performed forabout 1 hour at ambient temperature, although the mixture may beoptionally heated.

In another embodiment, the solid fraction is subjected to mild acidhydrolysis. Mild acid hydrolysis may be performed with an organic acid,a mineral acid, and combinations thereof, at an interdependentcombination of acid concentration, temperature, and time. It isappreciated that lower temperatures and/or lower acid concentrations mayrequire longer times for mild hydrolysis. Illustrative combinations ofthese three factors include: about 3% acid for about 1 h at 121° C.(autoclave temperature), about 1% to about 5% acid for about 1 h atabout 100° C. or greater, about 5% to about 10% acid for about 1 h atabout 90° C. or greater, about 10% to about 20% acid for about 1 h atabout 60 to about 90° C., and about 20% to about 30% acid for about 1 hor greater at less than about 60° C. It is appreciated that temperaturesabove 100° C. may require a pressure vessel for conducting the mild acidhydrolysis. For example autoclave temperatures (121° C.) typicallyinvolve about 14 psi of pressure.

The solid fraction may be solubilized and/or hydrolyzed under strongeracid conditions as described herein, then subsequently hydrolyzed undermilder acid conditions as described herein. In either case, theresulting treated waste stream may be subjected to an additionalsolid/liquid separation process to provide a treated liquid extract. Theremaining solid fraction may be discarded or recycled into thesolubilization and/or hydrolysis processes described herein.

In embodiments that include fermentation, the treated liquid wastestream or extract may be reintroduced to the liquid fraction removed atthe solid/liquid separation step. Depending upon the relative volumes ofeach fraction, namely the original liquid fraction and the extractliquid fraction resulting from the treatment step described herein, thepH may be adjusted to levels for optimal sterilization and/or pH levelsthat are optimal for the health, growth, and/or proliferation of thefermenting organism. For example, when the fermenting organism is ayeast, the optimal pH is illustratively in the range from about 4.0 toabout 4.5. If the pH is too high, additional acid, such as sulfuric acidmay be added. If the pH is too low, additional base, such as calciumoxide, calcium hydroxide, calcium carbonate, lime, and the like may beadded.

In some variations where a calcium containing base is added to adjustthe pH, calcium sulfate may form a precipitate. This precipitate may beoptionally removed before any sterilization or fermentation processes orapparatus. It is appreciated that in some situations, the precipitate isnot removed until after the fermentation to avoid inadvertent removal ofother nutrients that are useable by the fermenting organism, such asorganic acids and nitrogen containing components.

An illustrative embodiment of an apparatus 1700 and process for treatingwaste streams WS, including barn waste streams is shown in FIG. 44A. Theapparatus includes a first solid/liquid separation unit 1710A, which maybe any conventional solid/liquid separation system or the solid/liquidseparation unit described in PCT/US2005/______, entitled SYSTEM FORPROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no. 35479-77858)to generate a first liquid waste stream LW1 and one or more solid wastestreams SW. First solid/liquid separation unit 1710A includes aliquefied waste stream inlet LWI, a liquid outlet LO, and one or moresolid outlets SO. Illustratively, waste stream WS, which has beenoptionally pre-processed using one or more processes described herein orin PCT/US2005/______, entitled SAND AND ANIMAL WASTE SEPARATION SYSTEM(attorney docket no. 35479-77857) and PCT/US2005/______, entitled SYSTEMFOR PROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no.35479-77858) enters first solid/liquid separation unit 1710A throughinlet LWI. Waste stream inlet LWI is in fluid communication with wastesteam conduit 1712, which is in fluid communication with a waste streamsource WSS. First solid/liquid separation unit 1710A separates wastestream WS into a first liquid waste stream LW1 and one or more solidwaste streams SW. First liquid waste stream LW1 exits separation unit1710A through liquid outlet LO, which is in fluid communication with aliquid waste stream conduit 1716. First liquid waste stream LW1 isoptionally further processed, such as by fermentation as describedherein. At least one solid waste stream SW1 is a lower density and/orlarger particle solid waste stream that includes fiber, hay, bedding,straw, and other cellulosistic components. First solid waste stream SW1exits separation unit 1710A through solid outlet SO, which is coupledwith a solid conveyer 1714. Solid conveyer 1714 feeds first solid wastestream SW1 into lignin removal unit 1720. Lignin removal unit 1720includes one or more lignin removal tanks 1730 for removing lignin fromfirst solid waste stream SW1 to provide a second solid waste stream SW2,such as washed fiber.

Referring to FIG. 44C, each lignin removal tank 1730 includes a solidwaste stream inlet SWI, a clean water inlet CWI for supplying water toliquefy and wash first solid waste stream SW1, a lignin outlet LNO forremoving the lignin suspension, a wash water out WWO for removing washwater after lignin removal, and a solid waste outlet SWO for removingsecond solid waste stream SW2 after lignin has been removed. Each ligninremoval tank 1730 has a generally sloped bottom 1734 connected to solidwaste outlet SWO. Outlet SWO is coupled to a collection chamber 1736 atthe base of the removal tank 1730. An auger 1738, including a motor M,is coupled to collection chamber 1736 for removing first solid wastestream SW1 after lignin removal. Each lignin removal tank 1730 alsoincludes, a stirring unit 1732, including a motor M, for mixing waterand first solid waste stream SW1, and optionally a level or fill sensorfor determining when lignin removal tanks 1730 are filled.Alternatively, the fill of lignin removal tanks 1730 may be determinedby a known constant flow rate of solid waste SW and clean water CW, andthe known capacity of tanks 1730. The optional level or fill sensor mayillustratively be a pressure transducer which sends a signal to aprogrammable logic circuit controlling solid waste conveyer 1714. Uponreceiving a signal from pressure transducer PT that a given tank 1730 isfull, conveyer 1714 is stopped or is diverted to move solid waste SWinto a second or subsequent tank 1730.

In one illustrative embodiment, first solid waste stream SW1 fromconveyer 1714 enters first lignin removal tank 1730 through inlet SWI.When first lignin removal tank 1730 is filled to capacity, conveyer 1714diverts first solid waste stream SW1 to second lignin removal tank 1730.Lignin may be removed from first solid waste stream SW1 in first ligninremoval tank 1730 by suspending the undissolved solids, allowing theundissolved solids to settle, floating off the fine fiber, filtering thefiber, and like processes. In one aspect, clean water enters firstlignin removal tank 1730 through inlet CWI and the mixture is agitatedor stirred with stirring unit 1732. Inlet CWI is in fluid communicationwith a clean water conduit 1722 coupled to a clean water source CWS.Fill levels may be determined by using a timing algorithm that includesa predetermined fill rate and volume of removal tanks 1730, by theappropriate placement of a fill level sensor such as a pressuretransducer PT in removal tanks 1730, or by any other conventionalmethod. After removal tank 1730 is filled and after an optionalpredetermined dwell time, the stirring or agitation of the contents inremoval tanks 1730 is discontinued and the solid contents of the removaltank 1730 are allowed to settle. It is appreciated that the settling ofthe components making up first solid waste stream SW1 may followstandard Reynolds behavior where the smaller particles are concentratedtoward the top of the settled material, and the larger particles areconcentrated toward the bottom of the settled material. It isappreciated that such settling behavior is also dependent upon therelative density of the components making up the solid waste stream SW1,but where densities of various particles are similar, the settling ratewill typically be determined by particle size as described herein. Aftersettling, clean water is again introduced through inlet CWI in acountercurrent flow through the bottom of the settled material.

It is appreciated that in variations of removal tanks 1730 shown in FIG.44C, the countercurrent flow of water may enter through a dedicatedclean water inlet CWI, or through the same clean water inlet CWI used tofill removal tanks 1730. The water is introduced through clean waterinlet CWI at a predetermined velocity capable of suspending the smallerparticles, such as lignin particles, and leaving the larger particles,such as cellulose, hay, straw, and other cellulosistic material at thebottom of removal tanks 1730. It is understood that the smaller orfinely divided particles are generally lignin particles or solids thatmay not be as useful for the subsequent hydrolysis steps than are thelarger particles. Water flow is continued until a predetermined amount,illustratively a substantial amount, of the lignin is removed out thetop of the removal tank 1730 through lignin outlet LNO, at which timewater flow is discontinued. The remaining water in removal tanks 1730 isremoved through wash water outlet WWO, which is in fluid communicationwith lignin conduit 1724, and the wash water is combined with the liquidexiting lignin outlet LNO. The second solid waste stream SW2 is removedfrom lignin removal tanks 1730 using auger 1738. In one illustrativeembodiment, auger 1738 is vertically placed in collection chamber 1736.In another illustrative embodiment, auger 1738 is transverse tocollection chamber 1736. In another illustrative embodiment, auger 1738is fabricated from perfplate and allows water to through and aroundsecond solid waste stream SW2 as it is removed from tanks 1730. Secondsolid waste stream SW2 is moved onto conveyer 1726 and sent tosolubilization unit 1760.

The removed lignin exits each lignin removal tank 1730 through ligninoutlet LNO and is combined with wash water exiting wash water outlet WWOin lignin conduit 1724. Lignin conduit 1724 in fluid communication witha liquid waste inlet LWI on a second solid/liquid separation unit 1710B.

In aspects that include only one lignin removal tank 1730, the processis performed in a batch mode. In aspects that include more than onelignin removal tank 1730, the process is performed in a continuous mode,where one tank is filling while the remaining tank or tanks are instirring phase, a settling phase, a washing phase, a draining phase, ora second solid waste stream SW2 removal phase. In either case, eachlignin removal tank 1730 includes one or more valves V that may be eachoperated by a programmable logic circuit, controlling clean water entryinto inlet CWI, wash water exit out of outlet WWO, lignin suspensionexit out of outlet LNO, and the like. The algorithm controlling thedwell, filling, washing, settling, emptying, and fiber removal steps inthe lignin removal process may include an elapsed time parameter, aparameter dependent on sensing a fill level in the tank, othercomparable or conventional parameter for monitoring the lignin removalprocess, or a combination thereof.

Referring to FIG. 44A, illustratively, suspended lignin exiting throughexit port LNO, including water removed from removal tank 1730 throughwash water outlet WWO, enters second solid/liquid separation unit 1710B,where the removed lignin is separated from the liquid. Secondsolid/liquid separation unit 1710B includes a clean water inlet CWI influid communication with a clean water source via conduit 1728.Separation of the lignin may be accomplished by filtration,centrifugation, or by passing over a fine vibrating screen. The finevibrating screen may be any conventional vibrating screen, including avibrating screen assembly described herein. Illustratively, theseparated lignin is removed for disposal, and the liquid is nowclarified water and is sent to a lagoon, ordinary disposal streams, orto ground. Alternatively, the clarified water may be recycled into anyof the processes or apparatus described herein.

Referring to FIG. 44B, upon completion of lignin removal, second solidwaste stream SW2 enters solubilization unit 1760 via conveyer 1726.Solubilization unit 1760 includes one or more solubilization tanks 1770.In aspects that include only one solubilization tank 1770, the processis performed in a batch mode. In aspects that include more than onesolubilization tank 1770, the process is performed in a continuous mode,where one tank is filling while the remaining tank or tanks are in astirring phase, or a dwell phase. In either case, each tank 1770includes a solid waste stream inlet SWI, a solubilzed or liquefied wastestream outlet LWO, an acid inlet AI, and a stirring unit 1772 includinga motor M. Acid inlet AI is supplied by an acid source 1774, and bothacid source 1774 and inlet AI are in fluid communication with an acidconduit 1762. Solubilization tanks 1770 optionally include a fill orlevel sensor, such as a pressure transducer. Alternatively, fill may bepredetermined by operating the processes described herein at known flowrates using apparatus with known capacities. Each inlet and outlet ofsolubilization tanks 1770 is fitted with a valve V optionally coupled toand operated by a programmable logic circuit. The algorithm controllingthe filling and emptying of each tank 1770, including acid inlet AI,second solid waste stream SW2, and the solubilized waste outlet LWO, inthe solubilization process may include an elapsed time parameter, aparameter dependent on sensing a fill level in the tank, othercomparable parameter, or a combination thereof. Each solubilization tank1770 optionally includes a temperature sensor (not shown) and/or a heatexchanger (not shown). In such alternate embodiments, solubilzation maybe performed at a higher than ambient temperature.

In one illustrative process, second solid waste stream SW2 enters thesolubilization tanks 1770 through SWI, and acid is introduced intosolubilization tanks 1770 through acid inlet AI. Illustratively, acidsource AS contains about 95% sulfuric acid, and after addition, theconcentration of sulfuric acid in solubilization tanks 1770 is about72%. The contents are stirred with stirring unit 1772 for apredetermined period of time or until a predetermined measured parametersuch as a predetermined conductivity, optical density, or like parameterof the bulk contents of the solubilization tanks 1770 is observed andindicates solubilization of second solid waste stream SW2 to provide asecond liquefied waste stream LW2. At that time, second liquefied wastestream LW2 is removed through waste outlet LWO. Waste outlet LWO is influid communication with conduit 1764 which is also in fluidcommunication with acid hydrolysis unit 1780. It is appreciated that incertain variations of the solubilization process, some hydrolysis ofsecond solid waste stream SW2, including hydrolysis of washed fiber, mayalso occur during the solubilization process.

In variations of the solubilization unit 1760 described herein, eachtank 1770 is also fitted with a gas sparger (not shown) for removingoxygen from the solubilization process. It is understood that some acidsused in the solubilization process may be incompatible with dissolvedoxygen and may cause undesired side reactions, corrosion of the tanks,or other interfering events. Optional sparger is supplied by a gascapable of displacing or replacing the oxygen that is dissolved in thecontents of solubilization tanks 1770. In other variations, acid source1774 is also fitted with a gas sparger (not shown) for removing oxygen.In other variations, water supplied to the solubilization process hasbeen sparged to remove dissolved oxygen. In other variations, secondsolid waste stream SW2 is also sparged to remove dissolved oxygen beforeintroduction of the acid in solubilization unit 1760.

Conduit 1764 is fitted with a clean water inlet CWI in fluidcommunication with a clean water source via clean water conduit 1766.Second liquefied waste stream LW2 exiting liquefied waste outlet LWO isdiluted with water supplied by clean water inlet CWI in conduit 1764. Invariations of solubilization processes described herein, an optionalheat exchanger 1768 is coupled to conduit 1764 after clean water inletCWI and prior to acid hydrolysis unit 1780. It is appreciated thatduring dilution of the solubilized fiber with water, heat may beproduced, and in some variations this heat is advantageously removedprior to entry into acid hydrolysis unit 1780. It is understood thatthis heat may be captured and removed, and optionally used for othersteps or components of the processes or apparatus described herein thatrequire heat. Conduit 1764 may also fitted with a series of sensors,such as pH sensors, conductivity sensors, concentration sensors, and thelike, and combinations thereof. In one illustrative embodiment, a pairof conductivity sensors CS are coupled to conduit 1764 from which the pHof the second liquefied waste stream LW2 may be measured. A firstconductivity sensor CS1 is placed upstream of clean water inlet CWI, anda second conductivity sensor CS2 is placed downstream of clean waterinlet, and optionally downstream of heat exchanger 1768, and beforehydrolysis unit 1780. Periodic measurements of the pair of conductivitysensors may be used to control the amount or rate of addition of cleanwater into inlet CWI. An illustrative relationship between conductivityand pH was determined in Example 2, and FIG. 47 shows an illustrativegraphical representation of this relationship. Clean water inlet CWIused for diluting liquefied waste stream can be metered and controlledby an algorithm using the sensor data to introduce the appropriateamount of clean water into conduit 1764 to dilute second liquefied wastestream LW2 to achieve the predetermined acid concentration for entryinto hydrolysis unit 1780.

Hydrolysis unit 1780 includes one or more hydrolysis tanks 1790. Inaspects of hydrolysis unit 1780 that include only one hydrolysis tank1790, the process is performed in a batch mode. In aspects that includemore than one hydrolysis tank 1790, the process is performed in acontinuous mode, where one tank is filling while the remaining tank ortanks are in a dwell phase, a stirring phase, a heating phase, or anemptying phase. In either case, each hydrolysis tank 1790 includes aliquid waste inlet LWI, and a liquid waste outlet LWO. Inlet LWI is influid communication with conduit 1764 and positioned after optional heatexchanger 1768. Second liquefied waste stream LW2 enters each hydrolysistank 1790 through inlet LWI. After completion of the acid hydrolysisstep, a third liquid waste stream LW3 is provided, which exits eachhydrolysis tank 1790 through outlet LWO.

Referring to FIG. 44D, each hydrolysis tank 1790 includes a pair ofvalves V, optionally operated by a programmable logic circuit, thatcontrol flow into each hydrolysis tank 1790 through inlet LWI and flowout of each hydrolysis tank 1790 through outlet LWO. Each hydrolysistank 1790 has a generally sloped bottom 1796, and also includes astirring unit 1792, and an optional heating unit 1794. The algorithmcontrolling the filling, stirring, heating, and emptying of each tank1790 in the hydrolysis process may include an elapsed time parameter, aparameter dependent on sensing a fill level in the tank, temperaturesensor, other comparable parameter, or a combination thereof.Illustrative fill level sensors for use in the various apparatusdescribed herein, including hydrolysis tanks 1790, include pressuresensitive components, pressure transducers, ratio frequency levelsensors, weight sensitive components, and the like. Illustrativetemperature sensors for use in the various apparatus described herein,including hydrolysis tanks 1790, include thermocouples such as J-type,K-type, E-type, or T-type thermocouples.

In variations of hydrolysis unit 1780 described herein, each tank 1790is also fitted with a gas sparger (not shown) for removing oxygen fromthe hydrolysis process. It is understood that some acids used in thehydrolysis process may be incompatible with dissolved oxygen and maycause undesired side reactions, corrosion of the tanks, or otherinterfering events. The optional sparger is supplied by a gas capable ofdisplacing or replacing the oxygen that is dissolved in the contents ofhydrolysis tanks 1790. In other variations, water supplied to thehydrolysis process via inlet CWI in conduit 1764 has been sparged toremove or decrease the amount of dissolved oxygen.

In one illustrative embodiment, valve V to first hydrolysis tank 1790 isopened and second liquefied waste stream LW2 that has been diluted inconduit 1764 enters first hydrolysis tank 1790. Filling of firsthydrolysis tank 1790 may be monitored by a fill or level sensor, such asa pressure transducer, first hydrolysis tank 1790. Alternatively, usinga known tank capacity and a known flow rate, fill may be determined byelapsed time. After first tank 1790 is full, valve V to first tank 1790is closed, and valve V to second hydrolysis tank 1790 is opened andfilling begins in the second tank. Stirrer 1792 is operated and ifappropriate, heat exchanger 1794 is operated to raise the temperature ofthe contents of first hydrolysis tank 1790 to the predeterminedtemperature. A dwell phase ensues where hydrolysis proceeds to provide athird liquid waste stream LW3. After a predetermined period of time, oraccording to another algorithm used to assess the extent of hydrolysis,valve V controlling liquid waste outlet LWO of first hydrolysis tank1790 is opened, and third liquid waste stream LW3 is emptied from firsthydrolysis tank 1790. Similarly, after filling second hydrolysis tank1790, a dwell phase for hydrolysis is started, and the fillingsubsequent hydrolysis tank 1790 begins. It is understood that after thelast hydrolysis tank 1790 is filled, first hydrolysis tank 1790 reentersthe processing cycle.

Liquid waste outlet LWO of hydrolysis tanks 1790 is in fluidcommunication with a conduit 1782, which is in fluid communication witha liquefied waste inlet LWI of a third liquid/solid separation unit1710C. Third liquid/solid separation unit 1710C may be any conventionalsolid/liquid separation unit, including a solid/liquid separation unitdescribed herein, and may include a multiple-motor assembly capable ofvibrating a screen shaker in two independent directions, and a cleanwater inlet CWI in fluid communication with a clean water source viaconduit 1784, and used for washing the separated solids. Third liquidwaste LW3 enters third solid/liquid separation unit 1710C, where solidsare separated from third liquid waste LW3 to provide a fourth liquidwaste stream LW4 and one or more solid waste streams SW. The one or moresolid waste streams exit third solid/liquid separation unit 1710C viasolid waste outlet SWO. These solid waste streams may be disposed of ordiscarded in standard sanitary landfills. Alternatively, one or more ofthe solid waste streams may be recycled into the processes and apparatusdescribed herein for treating biomaterial waste streams. Fourth liquidwaste stream LW4 exits third solid/liquid separation unit 1710C vialiquid waste outlet LWO. Outlet LWO is in fluid communication with aliquid waste conduit 1718, which is in fluid communication with liquidwaste conduit 1716 exiting liquid waste outlet LWO of first solid/liquidseparation unit 1710A. Therefore, fourth liquid waste stream LW4 exitingthird solid/liquid separation unit 1710C is admixed with first liquidwaste stream LW1 exiting first solid/liquid separation unit 1710A.Combined liquid waste streams LW1 and LW4 may be further processed usingany conventional biomaterial waste processing system or apparatus,including the systems described herein and in co-filed applicationsreferenced herein, including additional processing by fermentation.

In embodiments where combined liquid waste streams LW1 and LW4 arefurther processed by fermentation, combined liquid waste streams LW1 andLW4 may enter a pH adjustment unit, then a sterilization unit, and thena fermentation unit. In processes and apparatus that include a pHadjustment step, that step may illustratively take place after thereintroduction of fourth liquid waste stream LW4 into first liquid wastestream LW1 to minimize the overall consumption of acid the process. Itis understood that in such processes, the amount of acid added in thesolubilization and hydrolysis steps is illustratively selected as abalance between efficient solubilization and hydrolysis of thecomponents and the ultimate pH needed for processes that includefermentation. It is also appreciated that the overall volume of thefourth liquid waste stream LW4 may often be substantially lower than theoverall volume of the first liquid waste streams LW1 exiting firstsolid/liquid separation unit 1710A. Therefore, even a mild acidhydrolysis solution, illustratively about 3% sulfuric acid, will havesufficient acid concentration to reduce the pH of the combined liquidwaste streams LW1 and LW4 to about the level necessary for fermentation,illustratively about 4 to about 5.

A pH adjustment unit may include an acid source and a base source foradjusting the pH of the incoming combined liquid waste streams.Generally, a pH adjustment unit lowers the pH of the buffered alkalinewaste, such as barn waste; however, in variations, a pH adjustment unitmay raise the pH of the liquid waste stream due to a relatively largeproportion of material coming from the processing of solid waste streamsby solubilization and hydrolysis, and entering a pH adjustment unitprior to fermentation. Suitable acids include inorganic or mineral acidssuch as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid,and acidic salts thereof, phosphoric acid, and acidic salts thereof, andthe like. Suitable bases include inorganic bases such as carbonates,sulfates, phosphates, ammonia, and sodium, potassium, calcium, and othersalts thereof, organic bases, and the like.

It is appreciated that the illustrative apparatus shown is FIGS. 44A,44B, 44C, and 44D are not restricted to treating barn waste, but isgenerally applicable to all animal-derived biomaterial waste streams. Itis also appreciated that for non-ruminant animal-derived biomaterialwaste streams, lignin removal unit 1720 forming part of the illustrativeapparatus shown is FIG. 44A may be optional and bypassed.

An illustrative embodiment of an apparatus 1800 and process for treatingswine waste streams is shown in FIG. 45A. Swine waste enters manurecollection unit 1810. Manure collection unit 1810 includes one or moreswine manure receptacles 1820 and a conveying unit 1814 for moving thecombined waste to a central site. It is understood that swine waste canbe concurrently collected or collected in batches by periodiccollection. It is appreciated that cultural practices may suggest thatthe swine herd is segmented to minimize the transmission of disease.Therefore, the periodic batch collection of SW may also be conducted ata plurality of sites into a plurality of swine manure receptacles 1820,as depicted in FIG. 45A. In variations of the processes described hereinwhere SW is collected concurrently or at a single site, it is understoodthat there may be only one receptacle 1820. In one aspect, eachreceptacle 1820 feeds into a pump P, such as a chopping pump, aprogressive cavity pump, and the like. In variations of the apparatusshown in FIG. 45A, each receptacle 1820 may not be fitted with a pump P,and the waste collected from the plurality of receptacles 1820 isconveyed to a centralized site having one or more pumps P.

In an alternate embodiment, conveying unit 1814 moves the collectedswine waste to a precipitation unit to precipitate proteins, includingproteins, organic acids, such as bile acids, and the like that may notbe metabolized or are otherwise unusable as nutrients by the fermentingorganism in order to recover valuable dissolved solids from LW. Aprecipitation unit may employ any of a variety of treatments orcomponents that facilitate the precipitation of dissolved solids or theaggregation of undissolved solids, including components such asaggregation catalysts, binders, binding agents, chelators, chelatingagent, treatments such as heat, pH changes, and the like, or acombination thereof.

Liquefied waste LW derived directly from collection at one orreceptacles 1820 or that exits a precipitation unit and enterssolid/liquid separation unit 1850, which may be any conventionalsolid/liquid separation system or the solid/liquid separation unitdescribed herein and in PCT/US2005/______, entitled SYSTEM FORPROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no. 35479-77858)to generate one more solid waste streams SWS and a liquid waste streamLWS. It is appreciated that SW may also be optionally preprocessed usingone or more processes described in PCT/US2005/______, entitled SAND ANDANIMAL WASTE SEPARATION SYSTEM (attorney docket no. 35479-77857) andPCT/US2005/______, entitled SYSTEM FOR PROCESSING A BIOMATERIAL WASTESTREAM (attorney docket no. 35479-77858) before entering thesolid/liquid separation unit 1850.

Solid/liquid separation unit 1850 includes a liquefied waste inlet LWI,a liquid waste stream outlet, LWO, and one or more solid waste streamoutlets SWO. First liquid waste stream LW1 is separated from one or moresolid waste streams SW in separation unit 1850, and exits separationunit 1850 via outlet LWO. Outlet LWO is in fluid communication with aconduit 1852. At least one solid waste stream outlet SWO is coupled witha conveyer 1854, and moves at least one solid waste stream, such as afirst solid waste stream SW1 to solubilization unit/hydrolysis unit1860. Solubilization unit/hydrolysis unit 1860 includes a solubilizationunit 1864, a hydrolysis unit 1866, and acid source 1862. Acid source1862 is coupled to solubilization unit 1864 via acid inlet AI.Solubilization unit 1864 and hydrolysis unit 1866 are in fluidcommunication via conduit 1868. Conduit 1868 is in fluid communicationwith clean water source CWI via conduit 1818. Illustratively,solubilization unit 1760, and hydrolysis unit 1780 shown in FIG. 44A anddescribed above are such variations that may be used in the apparatus ofFIG. 45A to solubilize first solid waste stream SW1 and provide secondliquid waste stream LW2, dilute second liquid waste stream LW2, andhydrolyze diluted second liquid waste stream LW2 to provide third liquidwaste stream LW3.

Following solubilization and hydrolysis, third liquid waste stream LW3exits solubilization unit/hydrolysis unit 1860 via outlet LWO and enterspump P, which is in fluid communication with a conduit 1874. Conduit1874 is in fluid communication with an enzyme source ES for supplying anenzyme or a mixture of enzymes to be admixed with third liquid wastestream LW3. Enzyme source ES may contain extracts of sprouted barley,malted barley, malted barley extract, sorghum extract, and the like.Conduit 1874 is also in fluid communication with a liquid waste inletLWI on a first enzymatic processing unit 1880A. First enzymaticprocessing unit 1880A includes one or more enzymatic processing tanks1890. If one enzymatic processing tank 1890 is included in the apparatusshown in FIG. 45A, the system is run in a batch mode. If more than oneenzymatic processing tanks 1890 are included in the apparatus shown inFIG. 45A, the system is run in a continuous mode. The control of such acontinuous mode parallels that described herein for multiple tankprocessing involving solubilization, hydrolysis, and the like. Eachenzymatic processing tank includes a liquid waste inlet LWI, a liquidwaste outlet LWO, a stirrer (not shown), an optional system for heatingand/or cooling the contents of enzymatic processing tanks 1890, such aswith heat exchangers, and optional temperature, conductivity, pH, fillor level sensors, pressure transducers, and the like for monitoring theenzymatic process performed in enzymatic processing tanks 1890.

Enzymatic processing results in a fourth liquid waste stream LW4 exitingeach enzymatic processing tank 1890, and first enzymatic processing unit1880A. Outlet LWO of enzymatic processing tanks 1890 is in fluidcommunication with outlet LWO of solid/liquid separation unit 1850 viaconduit 1852. Following enzymatic processing, fourth liquid waste streamLW4 exits first enzymatic processing unit 1880A and is admixed withfirst liquid waste stream LW1 in conduit 1852, and the mixture enterssecond enzymatic processing unit 1880B via conduit 1878. Secondenzymatic processing unit 1880B is configured similarly to firstenzymatic processing unit 1880A, and includes one or more enzymaticprocessing tanks 1890, which are configured similarly in both processingunits 1880A and 1880B.

In variations of the processes and apparatus shown in FIG. 45A, firstliquid waste stream LW1 is treated in a separate enzymatic processingunit 1880C, which is similarly configured. In other variations of theprocesses and apparatus described in FIG. 45A, third liquid waste streamLW3 exiting solubilization unit/hydrolysis unit 1860 is admixed withfirst liquid waste stream LW1 prior to enzyme source ES in conduit 1874.The combined first and third liquid waste streams LW1, LW3 entersenzymatic unit 1880A and treated as described above. In other variationsof the processes and apparatus shown in FIG. 45A, first liquid wastestream LW1 is not treated in an enzymatic processing unit before orafter first liquid waste stream LW1 is combined with fourth liquid wastestream LW4.

Combined liquid waste streams LW1 and LW4 may be further processed usingany conventional biomaterial waste processing system or apparatus,including the systems described herein and in co-filed applicationsreferenced herein, including additional processing by fermentation. Inembodiments where combined liquid waste streams LW1 and LW4 are furtherprocessed by fermentation, combined liquid waste streams LW1 and LW4 mayenter a pH adjustment unit, then a sterilization unit, and then afermentation unit.

An illustrative embodiment of a swine waste receptacle 1820 is shown inFIG. 45B. Receptacle 1820 may be any of a variety of sloped pan designs,and illustratively has an upper bin portion 1822 having vertical sides1824 each sloping inward, and a lower bin portion 1826 connected toupper bin portion 1822. Lower bin portion 1826 has vertical sides 1828each sloping inward and connecting to pan floor 1830, which is slopeddownward to outlet 1832.

In general, the one or more receptacles 1820 in the swine waste systemshown in FIG. 45A are each optionally fitted with a grate (not shown), aclean water inlet CWI, a vibrator or vibrating motor 1834, a levelsensor 1836, such as a ratio frequency (RF) level sensor capable ofdetecting liquid, at a low point in receptacle 1820, an auger feed 1838in fluid communication with outlet 1832, and a motor 1840 operatingauger feed 1838. The auger feed 1838 is in fluid communication with pump1842. Clean water enters receptacles 1820 through CWI, which optionallyincludes a sprayer or sparger 1844, and vibrator 1834 encouragesmovement and mixing of the collected waste into auger feed 1838, andsubsequently into pumps 1842, where it is further comminuted or pureedto provide liquefied waste stream LW. In general, the one or morereceptacles 1820 are each constructed with a sloped pan to assist themovement of waste into pumps 1842. It is appreciated that clean waterinlet CWI, sprayer 1844, vibrator 1834, auger feed 1838, and pump 1842are coordinated and may be operated to generate liquefied waste streamLW continuously or non-continuously, and non-continuous operation may beperiodic or intermittent according to an predetermined algorithm. Thealgorithm may take any or a variety of inputs including elapsed time,receptacle weight, receptacle fill level, pump torque profile, and thelike to initiate a collection sequence as described herein. For example,after a predetermined elapsed time, or after a receptacle 1820 reaches apredetermined fill level or predetermined gross weight, clean waterinlet CWI, sprayer 1844, vibrator 1834, auger feed 1838, and pump 1842are coordinately actuated for collection and generation of LW. Timedsequences may be regularly spaced throughout a 24-hour period, spacedmore frequently during daylight and less frequently at night, spacedmore frequently in conjunction with feeding times, and the like.Emptying is illustratively continued for a period of time correlatedwith the volume of receptacle 1820, until a minimum fill level isreached, or when the torque profile of the pump falls below apredetermined threshold value.

In another embodiment, the biomaterial waste stream is a variable anddilute biomaterial waste stream derived from food processing includingcheese processing, including whey, and the like. Whey is produced as abyproduct in cheese processing, and is primarily water and residualproteins, lactic acid, lactose, calcium, phosphorus, and othercontaminants. Many of the residual proteins, and the lactic acid andlactose cannot be used by certain fermenting organisms and is thereforeadvantageously removed or degraded in processes and apparatus thatinclude a fermentation process and/or apparatus, such as those describedherein.

An illustrative embodiment of an apparatus 1900 and process for treatingfood processing waste streams, such as whey, is shown in FIG. 46. A foodprocessing waste stream enters pH adjustment unit 1910 via pump P, andthen into protein precipitation unit 1920. Protein precipitation unit1920 may function by using aggregation catalysts, binding agents,complexing agents, chelating agents, or by using heat. Afterprecipitation, the food processing waste stream enters a solid/liquidseparation unit 1930, including any conventional solid/liquid separationsystem or the solid/liquid separation unit described herein and inPCT/US2005/______, entitled SYSTEM FOR PROCESSING A BIOMATERIAL WASTESTREAM (attorney docket no. 35479-77858) to generate one or more solidwaste streams SW and a first liquid waste stream LW1. Liquid wastestream LW1 exits separation unit 1930 via outlet LWO into conduit 1932in fluid communication with separation unit 1930. One or more solidwaste streams SW exit separation unit 1930 via outlet SWO into conduit1934 in fluid communication with separation unit 1930 and proteinhydrolysis unit 1950. Solid waste streams SW enter protein hydrolysisunit 1950 via solid waste inlet SWI. An auger 1940 coupled to conduit1934 may be included to move the one or more solid waste streams SW toprotein hydrolysis unit 1950. Protein hydrolysis unit 1950 is in fluidcommunication with a protein hydrolyzation agent source 1960, whichsupplies a protein hydrolyzation agent via pump P in fluid communicationwith both source 1960 and unit 1950, and agent inlet HAI coupled toprotein hydrolysis unit 1950. After protein hydrolysis has progressed topredetermined or otherwise acceptable levels, the hydrolyzed solid wastestreams SW result in a second liquid waste stream LW2, which exitshydrolysis unit 1950 via outlet LWO and into conduit 1952. Liquid wastestream LW2 may be removed from hydrolysis unit 1950 using a pump P.First liquid waste stream LW1 exiting solid/liquid separation unit 1930and entering conduit 1932 and second liquid waste stream LW2 exitingprotein hydrolysis unit 1950 and entering conduit 1952 are admixed.

Combined liquid waste streams LW1 and LW2 may be further processed usingany conventional biomaterial waste processing system or apparatus,including the systems described herein and in co-filed applicationsreferenced herein, including additional processing by fermentation. Inembodiments where combined liquid waste streams LW1 and LW2 are furtherprocessed by fermentation, combined liquid waste streams LW1 and LW2 mayenter a pH adjustment unit, then a sterilization unit, and then afermentation unit.

In another embodiment, the biomaterial waste stream is a variablebiomaterial waste stream derived from food processing including wasteoils and fats, such as cooking oils, deep frying fats, and the like.Waste oils and fats include glycerol-based fats, fatty acids, glycerols,and the like. Processes for treating such waste oils and fats includehydrolysis reactions, enzymatic degradations, and the like to degradethe fats and/or oils to components including glycerol and fatty or highmolecular weight organic acids. Hydrolysis reactions may be performed atacidic pH or at basic pH. In aspects including acidic pH treatment, thewaste oils and fats may be treated as described herein for treatingcellulosistic materials, such as by treatment with mineral acids,including hydrochloric, hydrobromic, and sulfuric acids. In embodimentsof the treatment processes described herein that include fermentation,the pH of the resulting treated waste may adjusted to the level requiredby the fermenting organism. In variations where the pH is either too lowof too high for the fermenting organism, the pH may be increased ordecreased in a pH adjustment step as described herein. It is appreciatedthat in some variations, the pH of the treated waste will be at or nearthat required by the fermenting organism, or may be pre-selected tomatch that required by the fermenting organism.

In aspects including basic pH treatment, the waste oils and fats may betreated with inorganic bases such as sodium hydroxide, potassiumhydroxide, calcium oxide, calcium hydroxide, sodium and potassium saltsof phosphate, sodium and potassium salts of carbonate, ammoniumhydroxide, and the like. In addition, catalytic amounts of organic basesmay be used, including amine bases such as DBU, DMAP, pyridine,lutidine, collidine, trialkylamines, and the like, in the presence ofinorganic bases such as those described herein. In aspects includingenzymatic treatment, the waste oils and fats may be treated with anenzyme capable of catalyzing the hydrolysis of esters, includingesterases, and the like. In embodiments of the treatment processesdescribed herein that include fermentation, the pH of the resultingtreated waste may adjusted to the level required by the fermentingorganism. In variations where the pH is either too low of too high forthe fermenting organism, the pH may be increased or decreased in a pHadjustment step as described herein. It is appreciated that in somevariations, the pH of the treated waste will be at or near that requiredby the fermenting organism, or may be pre-selected to match thatrequired by the fermenting organism. It is appreciated that whenammonium hydroxide is used as the base, recovery of the base from thetreated waste may be accomplished by evaporation. Similarly, if the pHis too high for a fermenting used in embodiments that includefermentation, the pH may be lowered by evaporation of ammonia from thetreated waste stream. In variations that include other inorganic bases,it is understood that pH adjustment will produce salts such as sodiumchloride, potassium chloride, and the like.

In variations of the processes described herein that includefermentation, it is appreciated that glycerol is often more readily usedas a carbohydrate by a fermenting organism than is the parent fat oroil. Therefore, such fermentation processes may require less stringentor less harsh conditions to effect fermenting organism proliferation, orpollution removal than would otherwise be required if the nutrientsource were not treated as described herein. It is further appreciatedthat two-stage fermentation processes, such as those described hereinmay be used to separately utilize the glycerol nutrient and the fattyacid nutrients. A fermenting organism that uses the glycerol nutrientmay be used in one fermentation step, and a fermenting organism thatuses the fatty acid nutrient may be used in the other fermentation step.It is further appreciated that the conditions for each nutrient use maybe selected to optimize the growth of the fermenting organism, tooptimize the utilization of the nutrient, and other desired end results.In one embodiment, the fermenting organism selected to use the fattyacid nutrient in one fermentation step is a Pichia species.

An illustrative embodiment of an apparatus 2000 and process for treatingfood processing waste streams, such as waste fats and oils, thatincludes a base hydrolysis or saponification process is shown in FIG.48. A food processing waste stream enters base solubilization unit 2010,which is fitted with a stirrer 2012, a clean water inlet CWI supplied byclean water source CWS via conduit 2015, a base inlet BI in fluidcommunication with a base source 2020 supplied via conduit 2014, asolubilized waste outlet SWO, and an optional heating unit (not shown).Solubilization unit 2010 is configured to allow a continuous processwhere the material that has been the unit 2010 for the longest period oftime is preferentially removed from unit 2010 through solubilized wasteoutlet SWO. In an alternate configuration, solubilization unit 2010includes a plurality of tanks 2030, and the process is run in a serialbatch mode that approximates a continuous operation, where while onetank 2030 is in a filling phase, the remaining tanks 2030 are in variousstages of stirring, heating, dwell, or emptying phases. Solubilizedwaste exiting waste outlet WO enters conduit 2018, which is in fluidcommunication with waste inlet WI coupled with hydrolysis unit 2040.Hydrolysis unit 2040 may include one or more hydrolysis tanks 2050.Processes and apparatus similar to those described above and shown inFIGS. 44A, 44B, 44C, and 44D may be adapted to such embodiments fortreating food processing waste streams in a solubilization unit and/or ahydrolysis unit. Conduit 2018 is also in fluid communication with cleanwater inlet CWI supplied by clean water source CWS via conduit 2016.Clean water is optionally admixed with waste exiting solubilization unit2010 to dilute the waste stream for hydrolysis in hydrolysis unit 2040.Conduit 2018 is also optionally fitted with a heat exchanging system2036. It is appreciated that admixing clean water via conduit 2016 andsolubilized liquefied waste in conduit 2018 may produce heat, which isoptionally dissipated or removed by heat exchanger 2036 prior to entryof diluted solubilized liquefied waste into hydrolysis unit 2040.Apparatus 2000 may also include a pair of conductivity sensors C coupledto conduit 2018. First conductivity sensor C is located upstream ofclean water inlet CWI and second conductivity sensor C is locateddownstream of clean water inlet CWI. The pair of conductivity sensors Care connected to a programmable logic circuit PLC capable of receiving asignal from conductivity sensors C related to the conductivity of awaste stream in conduit 2018 and calculating a pH or concentrationvalue. Depending upon the calculated pH or concentration value,programmable logic circuit PLC controls the amount of clean waterentering conduit 2018 used to dilute a waste stream exitingsolubilization unit 2040. It is appreciated that if optional heatexchanger 2036 is included in apparatus 2000, second conductivity sensorC is often located downstream of heat exchanger 2036 to decrease theimpact of a temperature variable on the calculation of the pH orconcentration value.

Following treatment in hydrolysis unit 2040, solubilized waste SWadmixed with an enzyme, such a lipase, and the like, supplied by enzymesource 2060 and enters enzymatic processing unit 2070. Enzymaticprocessing unit 2070 is fitted with an hydrolyzed waste input LWI, andan enzyme-treated waste outlet LWO. Prior to contact with the enzyme inenzymatic processing unit 2070, the pH of the solubilized waste SW maybe adjusted to a level optimum for the enzyme used in enzymaticprocessing unit 2070. Processes and apparatus similar to those describedabove and shown in FIG. 45 may be adapted to such embodiments fortreating food processing waste streams in an enzymatic processing unit.In embodiments of the waste oil and fat treatment described herein thatinclude a fermentation step, the material exiting enzymatic processingunit 2070 may enter a pH adjustment unit, a sterilization unit, and/or afermentation unit.

Analogous to other apparatus described herein, in variations of theprocesses and apparatus described herein for treating waste fats andoils, solubilization unit 2010, hydrolysis unit 2040, and/or enzymaticprocessing unit 2070 may each include more than one tank, vessel, orcontainer 2080 for performing the respective processing step. Thesealternate configurations allow the processes to be run in a serial batchmode that simulates a continuous process so that the supply of foodwaste FW is continuous to the apparatus shown in FIG. 48. In othervariations, either hydrolysis unit 2040 or enzymatic processing unit2070 is bypassed in the apparatus shown in FIG. 48.

EXAMPLE 2 Titration of Barn Waste with 98% H₂SO₄

A representative average sample of barn waste was adjusted to 4% solidsby weight (MM free). A 100 gallon (379 liter) aliquot of the 4% barnwaste slurry was titrated with 98% sulfuric acid, and the pH and theconductivity of the resulting mixture was measured as a function ofadded acid. The results of the titration are shown in FIG. 47. As the pH(diamonds) decreased with added acid, the conductivity (squares,millisiemens) increased. The barn waste began as an alkaline mixture. Itwas also observed that the components of the barn waste buffered thesolution to pH change. As the pH of the mixture approached neutrality,the conductivity measurement formed a first plateau. As the pH changedthrough the pK_(a) range of most organic acid components included in thebarn waste (pH 5.5-3.5), the conductivity formed another plateau,indicative of buffering. As the pH decreased below about 3.5, theconductivity increased rapidly. The first plateau of observedconductivity may be used in algorithms described herein to halt pHadjustment at about pH neutrality, such as in the processes andapparatus described herein for precipitating salts from aqueoussolutions. The second plateau of observed conductivity may be used inalgorithms described herein to halt the pH adjustment at about 4 toabout 4.5, such as in the processes and apparatus described herein forsterilization, fermentation, and the like where the pH is optimallyadjusted in the range from about 4 to about 4.5. About 0.12 to about0.15 gallon (0.4543 to about 0.5678 liter) of sulfuric acid was neededto reach this pH range.

EXAMPLE 3 Compositions of Illustrative Biomaterial Waste Streams

Table 4 illustrates representative compositions of horse, dairy, swine,and poultry waste streams. TABLE 4 Manure and urine analysis per 1000pounds of animal.^((a)) horse dairy beef swine layer broiler human wet50 80 51.2 63.4 60.5 80 30 weight^((b)) % water 78 87.5 88.4 90 75 7589.1 dry total 11.0 10.0 6.34 15.1 solids^((c)) COD^((d))   ND^((e))8.90 6.06 13.7 BOD(5)^((f)) ND 1.60 2.08 3.70 N 0.28 0.45 0.3 0.42 0.831.1 0.2 P 0.05 0.07 0.09 0.16 0.31 0.34 0.02 K 0.19 0.26 0.22 0.34 totalND 0.85 1.29 2.89 dissolved solids^((g)) C/N^((h)) 19 10 7 7 AU^((i)) 10.74 1 9.09 250 455 8^((a))Data from 40CFR., US Environmental Protection Agency; averagehuman weight in US of 125 pounds; data on generation rates, moisturecontent, nitrogen, and phosphorus from Agricultural Waste ManagementField Handbook. USDA Natural Resource Conservation Service, Chapter 4(April 1992); dairy is lactating cow; beef on high energy diet; swinerefers to growers; layers and broilers refer to poultry;^((b))pounds/day/1000# animal;^((c))determined by evaporation using standard EPA protocols;^((d))chemical oxygen demand as determined using standard EPA protocols;^((e))ND = not determined;^((f))biological oxygen demand as determined using standard EPAprotocols;^((g))determined by passing the waste a 0.45 μm filter, and evaporatingthe filtrate; includes suspended solids smaller than 0.45 μm in size;^((h))carbon/nitrogen ratio;^((i))number of animals per 100 pounds.

The data shown in Table 4 are illustrative, but it is appreciated thatdue to feed regimen, season, nutrition, animal location, animallactation status, and many other variations, these data may varysubstantially.

EXAMPLE 4 Predicted Results of Processing Illustrative Biomaterial WasteStreams

Table 5 illustrates the calculated nitrogen, phosphorus, and potassiumrequired for conversion of horse, dairy, swine, and poultry wastestreams. TABLE 5^((a)) horse dairy swine poultry COD 1^((b)) 2.0 3.3 1.22.6 COD 2^((c)) 5.7 3.3 4.8 11 Total COD 7.7 6.6 6.1 14 required 0.320.32 0.24 0.54 nitrogen^((d)) excess (deficit) nitrogen^((e)) (0.04)0.13 1.84 0.29 nitrogen used  100% 72.0% 57.6% 65.3% required 0.0500.050 0.038 0.084 phosphorus^((d)) excess 0 0.02 0.38 0.23phosphorus^((e)) phosphorus 99.5% 71.7% 23.4% 27.1% used required 0.0580.059 0.044 0.098 potassium^((d)) excess potassium^((e)) 0.13 0.20 0.120.24 potassium used 30.5% 22.5% 19.9% 28.8%^((a))Dairy is lactating cow; swine refers to growers; poultry refers tolayers; values given in pounds/day/1000# animal;^((b))chemical oxygen demand of first extract diluted to 4% by weightsolids content, as determined using standard EPA protocols;^((c))chemical oxygen demand of second extract corrected to original 4%by weight solids content, as determined using standard EPA protocols;^((d))values calculated based on complete conversion of total COD;^((e))values calculated based on average amount in animal waste stream.

The horse, dairy, swine, and poultry waste streams were diluted to about4% solids content. The first extract from each waste stream was obtainedby settling the corresponding waste for 1 minute and decanting thesupernatant liquid. It has been observed that this technique givessimilar results to a shaker screen separation. In contrast,centrifugation removes a greater amount of solids, including bacteria.Chemical Oxygen Demand (COD) of the supernatant liquid was determinedwith standard EPA testing protocols. Fresh, representative scrapings arediluted to approximately 4% solid (total including suspended anddissolved, but excluding sand and minerals including NaCl, and otherpure inorganic compounds, concentration relative to moisture and an ashfree weight determination. The percentage of sand and un-dissolvedsolids is estimated by re-dissolving ash residues and decanting.

The first extract was obtained as in Example 3. Washed fiber from eachwas generated by overflow wash of settled fiber. Water was introducedinto a cylinder such that the terminal velocity (settling speed) ofligneous and small cellulose containing fibers was exceeded by theupward velocity of the liquid, leaving only heavy or large fibermaterial in the flask. The second extract was obtained by exposing theheavy or large fiber to 72% sulfuric acid at ambient temperature for 60minutes, then diluting to about 3% and heating to 121° C. (autoclavetemperature) for 60 minutes. Residual ligneous material was removed. Thesecond extract was added to the first extract and if necessary the pHwas adjusted to 4.5 with calcium carbonate. Precipitated calcium sulfatewas removed. Calcium carbonate in the form of lime rock facilitated theremoval of the calcium sulfate and the ligneous material.

EXAMPLE 5 Predicted Results of Processing Illustrative Biomaterial WasteStreams with Added Malted Barley

Table 6 illustrates the calculated nitrogen, phosphorus, and potassiumrequired for conversion of horse, dairy, swine, and poultry wastestreams after addition of malted barley as an additional source ofcarbohydrate. TABLE 6^((a)) horse dairy swine poultry COD 1^((b)) 2.03.3 1.2 2.6 barley COD added^((c)) — 3.2 6.0 6.0 COD 2^((d)) 5.7 3.3 4.811 Total COD 7.7 9.8 12.1 19.7 required nitrogen^((e)) 0.32 0.45 0.470.77 excess (deficit) nitrogen^((f)) (0.04) (0.04) (0.13) (0.02)nitrogen used  100% 99.1%  100% 92.9% required phosphorus^((e)) 0.0500.069 0.073 0.12 excess phosphorus^((f)) 0 0 0.09 0.19 phosphorus used99.5% 98.8% 45.6% 38.5% required potassium^((e)) 0.058 0.081 0.085 0.14excess potassium^((f)) 0.13 0.18 0.13 0.20 potassium used 30.5% 31.0%38.7% 50.0%^((a))Dairy is lactating cow; swine refers to growers; poultry refers tolayers; values given in pounds/day/1000# animal;^((b))chemical oxygen demand of first extract diluted to 4% by weightsolids content, as determined using standard EPA protocols;^((c))barley also includes additional nitrogen, phosphorus, andpotassium;^((d))chemical oxygen demand of second extract corrected to original 4%by weight solids content, as determined using standard EPA protocols;^((e))values calculated based on complete conversion of total COD;^((f))values calculated based on average amount in animal waste stream.

As can be calculated from Table 5, 3.1 pounds of yeast wouldtheoretically result from 1000 pounds of swine waste. However, only 23%of the available phosphorus is utilized. By addition of about 5 poundsof malt to the process, as illustrated in Table 6, 6.1 pounds of yeastwould be theoretically produced, using 45.6% of the phosphorus(corrected for the additional phosphorus included by adding barley). Itis appreciated that as much as 50% of the phosphorus may be in the formof phytic acid arising from the corn and soy feed. Corn and soy feed areoften used as a replacement for inorganic phosphorus as a foodsupplement in dairy, beef, swine, and other animal feeds. It isunderstood that feeding animals a yeast, including a yeast produced inthe fermentation processes described herein may eliminate otherphosphorus supplementation, including corn and soy feed, and thereforeless phosphorus may be in the form of phytic acid. Illustratively, 6.1pounds of yeast replaces more than 6.1 pounds of soy protein andeliminates phosphate replacement as a feed supplement. Subsequentutilization of phosphate by swine may consequently move to levels higherthan the observed 45.6%. The data in Table 6 show that nitrogen is thelimiting nutrient, while the data in Table 5 show that COD is thelimiting nutrient. Accordingly, it is understood that in order toincrease phosphorus consumption, a suitable nitrogen source may besupplied to the fermenting organism, such as gaseous ammonia, ammoniumhydroxide, and the like. It is further understood that increasing boththe COD, such as by adding corn syrup, molasses, and the like, andnitrogen, such as by adding gaseous ammonia, ammonium hydroxide, and thelike, supplied to the fermenting organism, increased consumption ofphosphorus can be achieved.

EXAMPLE 6 Predicted Yeast Production and Removal of Nutrients/Pollutants

It is appreciated that yeast production is dependent upon thecomposition of nutrients available in the waste. A 4% w/w total solids(40 grams per liter) barn waste slurry was separated into a first liquidstream and a first solid stream. The COD of the first liquid stream(first extract) was 13.4 g/L. The first solid stream consisted primarilyof cellulosistic waste including fiber. The cellulosistic waste waswashed, and gave 15 g/original Liter of 4% material. The washed fiberwas degraded with sulfuric acid in a two-stage process, and separatedinto a second liquid stream and a second solid stream. The COD of thesecond liquid stream (second extract) was 10.0 g/original L. Inaddition, the stream analyzed for phosphorus at 0.28 g/original L(0.007%), and nitrogen at 1.6 g/L (4%).

Yeast production from the first extract was 1 g yeast for each 1.1 gCOD. The production rate of yeast from the first extract was calculatedto be 4,187 g/min (9.2 pounds/min), based on a 379 L/min flow rate (100gallon/min), 13.4 g COD, and 1.2 conversion rate (adjusted forinefficiency by 0.1). Yeast production from the second extract was 1 gyeast for each 2.2 g COD. The production rate of yeast from the secondextract was calculated to be 1,630 g/min (3.6 pounds/min) based on a 379L/min flow rate (100 gallon/min), 10 g COD, and 2.3 conversion rate(adjusted for inefficiency by 0.1). It is understood that the productionrate from the first extract may be higher due to the presence of organicacids, urea, amino acids, lipids, and other valuable nutrients. Incontrast, it is understood that the production rate from the secondextract may be lower because the major nutrients are carbohydrate, as isconsistent with conventional conversion rates for sugar, 1 g yeast foreach 2.2 g sugar. It is further understood that production rates for thesecond extract may be improved in barn waste streams containing biomassbedding, such as straw, hay, sawdust, and the like. For example, haycontains significant protein that may improve yeast production.

EXAMPLE 7 Predicted Pollution/Nutrient Removal

An assay of a representative sample of yeast produced in 1 minute usingthe processes and with the apparatus described herein shows 7.5%nitrogen, 1.5% phosphorus, and 1.8% potassium. An assay of arepresentative sample of barn waste flowing at 379 L/min (100gallons/min) shows 600 g of nitrogen, 150 grams of potassium, and 105grams of phosphorus. The pollutant removed can be calculated, and isshown in Table 7. TABLE 7^((a)) nutrient source Yeast nitrogen potassiumphosphorus first extract 4187 314 75.4 62.8 second extract 1630 122 29.324.5 totals 5817 436 105 87.3 total nutrient^((b)) — 600 150 105 %removed — 73 70 83^((a))Values given in grams;^((b))amounts available in 100 gallons (379 liters) of barn waste.

Illustrative Embodiments of a Fermenter and Fermentation Method

The method described herein is a method useful for treating abiomaterial waste stream to remove pollutants in the biomaterial wastestream by converting the pollutants to a valuable product. In oneembodiment a biomaterial waste stream is subjected to oxidativefermentation in the presence of a microorganism (i.e., a fermentingorganism) to convert the pollutants in the biomaterial waste stream to avaluable product. Accordingly, at least a portion of the pollutants(e.g., phosphorous, nitrogen, and potassium) is removed from thebiomaterial waste stream and incorporated into the valuable product, forexample, the microorganism, reducing environmental pollution. In oneembodiment, fermentation of the biomaterial waste stream by thepresently described method results in the production of a valuableprotein product (e.g., a microorganism such as a yeast) that can beused, for example, as an animal feed additive, a feed supplement, afertilizer, a fertilizer ingredient, or a soil conditioner.

As used in this application, “microorganism” and “fermenting organism”are interchangeable.

Exemplary biomaterial waste streams that can be treated in accordancewith the method described herein include, but are not limited to,manure, cellulosistic solid waste, whey broth from cheese production orbiomaterial waste streams from other foodstuffs, broth remediation fromalcohol or yeast production, tannery waste, slaughterhouse waste, tallowwaste from rendering processes, waste derived from plants, and land fillwaste. The waste derived from plants can be, for example, waste fromhay, leaves, weeds, or wood and can be, for example, yard waste,landscaping waste, agricultural crop waste, forest waste, pasture waste,or grassland waste. The waste derived from foodstuffs can be fruit andvegetable processing waste, fish and meat processing wastes, bakeryproduct waste, and the like. In embodiments where the biomaterial wastestream is manure, the manure can be from an animal, for example, such asa human, a bovine animal, an equine animal, an ovine animal, a porcineanimal, or poultry. In one embodiment the biomaterial waste stream is avariable and dilute biomaterial waste stream derived from animal manureor human waste. In general, any organic biomaterial waste streamcontaining proteins, simple or complex carbohydrates, or lipids, or acombination thereof, can be fermented by using the presently describedmethod.

In one embodiment, the product generated is the microorganism (i.e., afermenting organism) that contacts the biomaterial waste stream, and themicroorganism utilizes the pollutants in the biomaterial waste stream(e.g., potassium, nitrogen, and phosphorus) as nutrients and removes thepollutants from the biomaterial waste stream. Illustratively, theproduct generated can be used as an animal feed, an animal feedsupplement, a fertilizer, a fertilizer ingredient, or a soilconditioner.

An exemplary technique that can be used to estimate the potentialcapacity for removal of pollutants from the biomaterial waste stream isa chemical oxygen demand (COD) measurement. A COD measurement can beaccomplished by estimating oxygen demand by oxygenation of compounds inthe presence of an indicator of the oxygenation, and techniques for CODmeasurement are known in the art. A COD measurement provides an estimateof the quantity of compounds that may potentially be removed from thebiomaterial waste stream by oxidative techniques. A COD measurement maybe made, during, before, or after the fermentation process as ameasurement of the extent of completion of removal of potentialpollutants.

The microorganisms (i.e., fermenting organisms) that contact thebiomaterial waste stream can be, for example, bacteria, yeast, fungi,mycoplasma, and combinations thereof, that utilize the pollutants in thebiomaterial waste stream as nutrients. Yeast species that can be used inthe presently described method include such yeast species asSaccharomyces species, Zygosaccharomyces species, Candida species,Hansenula species, Kluyveromyces species, Debaromyces species, Nadsoniaspecies, Lipomyces species, Torulopsis species, Kloeckera species,Pichia species, Yersinia species, Schizosaccharomyces species,Trigonopsis species, Brettanomyces species, Cryptococcus species,Trichosporon species, Aureobasidium species, Phaffia species,Rhodotorula species, Yarrowia species, Schizosaccharomyces species,Karwinskia species, Torulospora species, Schwanniomyces species, or anyother yeast species that is capable of fermenting organic waste. Variousyeast species are described in N. J. W. Kreger-van Rij, Biology ofYeasts, Vol. 1, Chap. 2, A. H. Rose and J. S. Harrison, Eds. AcademicPress, London, 1987, incorporated herein by reference.

Bacterial species that can be used in the presently described methodinclude, for example, Proteus species, Klebsiella species, Providenciaspecies, Yersinia species, Erwinia species, Enterobacter species,Salmonella species, Serratia species, Aerobacter species, Escherichiaspecies, Pseudomonas species, Shigella species, Vibrio species,Aeromonas species, Campylobacter species, Streptococcus species,Staphylococcus species, Lactobacillus species, Micrococcus species,Moraxella species, Bacillus species, Bordetella species, Enterococcusspecies, Propionibacterium species, Streptomyces species, Clostridiumspecies, Corynebacterium species, Eberthella species, Micrococcusspecies, Mycobacterium species, Neisseria species, Haemophilus species,Bacteroides species, Listeria species, Erysipelothrix species,Acinetobacter species, Brucella species, Pasteurella species, Vibriospecies, Flavobacterium species, Fusobacterium species, Streptobacillusspecies, Calymmatobacterium species, Legionella species, Treponemaspecies, Borrelia species, Leptospira species, Actinomyces species,Nocardia species, Rickettsia species, and any other bacterial speciesthat is capable of fermenting organic waste.

Examples of fungi that can be used in the presently describedfermentation method include, but are not limited to, fungi that grow asmolds or are yeastlike, including, for example, fungi that causediseases such as ringworm, histoplasmosis, blastomycosis, aspergillosis,cryptococcosis, sporotrichosis, coccidioidomycosis,paracoccidioidomycosis, mucormycosis, chromoblastomycosis,dermatophytosis, protothecosis, fusariosis, pityriasis, mycetoma,paracoccidioidomycosis, phaeohyphomycosis, pseudallescheriasis,sporotrichosis, trichosporosis, pneumocystis infection, and candidiasis.

In one embodiment, the microorganism (i.e., a fermenting organism) thatcontacts the biomaterial waste stream can be a thermophilicmicroorganism. In another embodiment, the microorganism can be amicroorganism that is not thermophilic. The microorganism can benaturally present in the biomaterial waste stream or the biomaterialwaste stream can be inoculated with the microorganism.

The microorganism can be partially or completely flocculated, and themicroorganism can be artificially or naturally flocculated. Inembodiments where the microorganism is artificially flocculated, aflocculating agent of a cationic type can be used in combination with aflocculating agent of an anionic type to catalyze flocculation. Theflocculating agent of the cationic type can be selected from the groupincluding ferrous chloride, ferrous sulphate, ferric chloride, ferricsulphate, chlorinated ferric sulphate, aluminium sulphates, chlorinatedbasic aluminium sulphates, magnesium chloride, magnesium sulphate, andcombinations thereof, and the like, or other cationic flocculatingagents described in more detail herein.

The flocculating agent of the anionic type can be selected from thegroup including an anionic polyacrylamide, a polyacrylate, apolymethacrylate, a polycarboxylate, a polysaccharide (e.g., xanthangum, guar gum or alginate), chitosan, cellulose, and combinationsthereof, and the like, or other anionic flocculating agents described inmore detail herein. A mixture of flocculating agents of the cationicand/or the anionic type can also be used. In one embodiment, themicroorganism is artificially flocculated using ferric chloride andxanthan gum. A method of catalyzing the flocculation of microorganismsis described more fully herein and in PCT/US2005/______, entitledFLOCCULATION METHOD AND FLOCCULATED ORGANISM (attorney docket no.35479-77852) incorporated herein by reference.

Illustratively, the fermentation unit 580 for use in the present methodcan be an air-lift fermenter and the fermentation method can becontinuous flow fermentation where the fermentation is oxidativefermentation, and the fermentation is made oxidative by injectingsterilized air into the fermentation unit 580. In one embodiment, thefermentation unit 580 is cylindrical and the highest concentration ofmicroorganisms is in the bottom half of the cylinder.

In another embodiment, the fermentation unit 580 can have an upwardlyopening cone 890 at the bottom of the fermentation unit 580 forcollection of the microorganism, and the lower portion of the upwardlyopening cone 890 can be tapered for collection of the microorganism inthe tapered region of the cone 890 for removal of the microorganism fromthe fermentation unit 580 through the product outlet port.

In one embodiment, the fermentation unit 580 can have a primary airinlet F10 to inject air into the fermentation unit 580 at a locationoutside of the cone 890 to circulate the microorganisms in thefermentation unit 580. In another embodiment, the cone 890 can have asecondary air inlet 898 to inject air into the cone 890. The injectionof air into the cone 890 can remove at least a portion of themicroorganisms that have collected in the cone 890 out of the cone 890so that the concentration of microorganisms in the cone 890 is reduced.As a result, the amount of the microorganism that is removed from thefermentation unit 580 after collection in the cone 890 is reduced.

An exemplary system for the fermentation of a biomaterial waste stream,including the fermentation unit 580 that is part of the system, isdescribed in detail herein and in PCT/US2005/______, entitled SYSTEM FORPROCESSING A BIOMATERIAL WASTE STREAM (attorney docket no. 35479-77858)incorporated herein by reference.

One or more fermentation units 580 can be employed in the present methodand, if more than one fermentation unit 580 is used, the fermentationunits 580 are in fluid communication with each other. The fermentationunit 580 for use in the present method can be used directly on the siteof an agricultural operation, if the system and method are used for thefermentation of animal manure, and can be adapted to any size animalfeeding operation or to any size community, or to any type ofbiomaterial waste stream.

In one embodiment, the method includes the step of subjecting thebiomaterial waste stream to conditions conducive to aerobic fermentationof the biomaterial waste stream. Illustratively, the conditionsconducive to fermentation can include an oxygen level in thefermentation unit 580 that is hyperbaric in the region of thefermentation unit 580 containing the highest concentration of themicroorganism (e.g., the bottom of the cylinder depicted in FIG. 20). Inother embodiments, the conditions conducive to fermentation can includemaintaining the biomaterial waste stream at a pH level of from about 2.0to about 10.0 and/or maintaining the temperature of the biomaterialwaste stream at a temperature of from about 15o C to about 80oC. Theconditions conducive to fermentation can be monitored by, for example,monitoring the conductivity, the temperature change (i.e. monitoring theamount of cooling required to maintain the temperature), or the gasvolume/mass of the biomaterial waste stream. An exemplary system for thefermentation of a biomaterial waste stream, including the sensors andcontrols for monitoring the conductivity, the temperature change, or thegas volume/mass of the biomaterial waste stream, is described more fullyherein and in PCT/US2005/______, entitled SYSTEM FOR PROCESSING ABIOMATERIAL WASTE STREAM (attorney docket no. 35479-77858) incorporatedherein by reference.

The fermentation method can also be optimized by maintainingsteady-state proliferation of the microorganisms resulting in efficientfermentation of the biomaterial waste stream. In embodiments where thebiomaterial waste stream is variable and dilute, the steady-stateproliferation of the microorganisms can be maintained by monitoring theconductivity, the temperature change (i.e., monitoring the amount ofcooling required to maintain the temperature), or the gas volume/mass ofthe biomaterial waste stream, and combinations thereof, and byincreasing or decreasing the amount of microorganisms in thefermentation unit 580. The amount of the microorganisms in thefermentation unit 580 can be adjusted, such as by removing a portion ofthe microorganisms from the fermentation unit 580 intermittently orcontinuously.

For example, in the embodiment where flocculated microorganisms areused, the flocculated microorganisms settle in the cone 890 and can beremoved from the fermentation unit 580 through the product outlet port.In one embodiment, the flocculated microorganisms can be removed fromthe fermentation unit 580 through the product outlet port independentlyof the biomaterial waste stream due, in part, to settling andcompression of the flocculated microorganisms in the cone 890 and theproduct outlet port. In this embodiment, if it is necessary to reducethe amount of flocculated microorganisms removed from the fermentationunit 580 and to allow the microorganisms to accumulate in thefermentation unit 580 to maintain steady-state proliferation, air can beinjected into the secondary air inlet 898 to inject air into the cone890. The injection of air into the cone 890 removes, out of the cone 890and the product outlet port, at least a portion of the flocculatedmicroorganisms that are settling and compressing in the cone 890 and theproduct outlet port so that the concentration of microorganisms in thecone 890 and the product outlet port is reduced. As a result, the amountof flocculated microorganisms removed from the fermentation unit 580through the product outlet port is reduced and the amount ofmicroorganisms that remain in the fermentation unit 580 is increased.

In another embodiment, if it is necessary to increase the amount offlocculated microorganisms removed from the fermentation unit 580, airinjection into the secondary air inlet 898 can be stopped to allow theflocculated microorganisms to settle and compress in the cone 890 andthe product outlet port. As a result, the amount of flocculatedmicroorganisms removed from the fermentation unit 580 through theproduct outlet port is increased and the amount of microorganisms in thefermentation unit 580 is decreased.

In the embodiment of the presently described fermentation method whereflocculated microorganisms are used, the capacity to control the amountof flocculated microorganisms removed from the fermentation unit 580,and to remove flocculated microorganisms from the fermentation unit 580independently of the biomaterial waste stream, allows for steady-stateproliferation to be maintained when the biomaterial waste stream beinginjected into the fermentation unit 580 has variable nutrient content.Because the flocculated microorganisms can be removed from thefermentation unit 580 independently of the biomaterial waste stream,steady-state proliferation of the microorganisms can be maintained inthe fermentation unit 580 due to the ability to control the amount ofmicroorganisms in the fermentation unit 580 relative to the amount ofnutrient in the variable biomaterial waste stream present in thefermentation unit 580 at any one point in time. The ability to maintainsteady-state proliferation of the microorganisms can result in efficientconversion (i.e., reproduction) of the microorganisms in thefermentation unit 580. In this embodiment, the steady-stateproliferation of the microorganisms can also be maintained by monitoringthe conductivity, the temperature change, and the gas volume/mass of thebiomaterial waste stream, and combinations thereof, because theseparameters are indicative of the state of proliferation of themicroorganisms in the fermentation unit 580.

As discussed above, a valuable product (i.e., the microorganisms) isproduced according to the presently described method. After removal ofthe microorganisms (i.e., the product) from the fermentation unit 580,the microorganisms can be preserved using any method known in the artfor preventing degradation of microorganisms and/or their proteincomponents. For example, the microorganisms can be pasteurized or themicroorganisms can be refrigerated or frozen after removing themicroorganisms from the fermentation unit 580. Alternatively, themicroorganisms can be degraded or partially degraded.

The microorganisms can be used as a valuable product in the form of, forexample, a paste, or another aqueous mixture, or a dry powder. Thepaste, aqueous mixture, or dry powder contains various nutrients andproteins that are suitable, for example, for use as an animal feedadditive or an animal feed supplement or for use as a fertilizer, afertilizer ingredient, or a soil conditioner. In an alternateembodiment, the wet product removed from the fermentation unit 580 canbe used without further processing.

The system for processing a biomaterial waste stream according to themethod described herein has a waste fermentation system 10, including,among other components, a fermentation unit 580, for converting thebiomaterial waste stream to a valuable product. For a more detaileddescription of the fermentation system 10 and illustrative embodiments,including a more detailed description of the fermentation unit 580 whichis a component of the system, see this application and PCT/US2005/______entitled SYSTEM FOR PROCESSING A BIOMATERIAL WASTE STREAM (attorneydocket no. 35479-77858).

Generally, the waste fermentation system 10 has a liquid waste inlet forreceiving the biomaterial waste stream, a product outlet port forremoving the microorganism and a liquid outlet for removing the residualbiomaterial waste stream liquid (i.e., the treated biomaterial wastestream from which pollutants have been removed). A number of sensors canbe provided to produce sensory information relating to operation of thewaste fermentation system 10. A controller can be provided to monitorthe sensory information, and the controller can be configured to controlthe waste fermentation system 10 based on the sensory information. Thesystem can further include a number of actuators each responsive to adifferent actuator control signal to modify operation of the wastefermentation system 10, and the controller can be configured to producethe number of different actuator control signals based on the sensoryinformation. The biomaterial waste stream can be provided in the form ofa continuous flow of liquid biomaterial waste, and can have variablenutrient content. The system controller can accordingly be configured tocontrol the waste fermentation system 10, based on the sensoryinformation, to controllably remove the microorganism while the nutrientcontent in the continuous stream of biomaterial waste is varying.

The system can further include a waste pretreatment system having aliquid waste inlet for receiving biomaterial waste and a liquid wasteoutlet for producing the biomaterial waste stream, wherein the wastepretreatment system is operable to treat the biomaterial waste andsupply the resulting biomaterial waste stream to the fermentation unit580. The waste pretreatment system can include a separation unit 18 forseparating waste solids from the biomaterial waste and producing aresulting liquid waste stream. The waste pretreatment system can includea pH adjustment unit 38 for modifying the pH level of the liquid wastestream to produce the biomaterial waste stream having a target pH.

The system can further include a waste post-treatment system having aninlet port for receiving the residual biomaterial waste stream liquid(i.e., the fermented biomaterial waste stream), a product outlet portand a liquid outlet port for producing a cleaned liquid stream, whereinthe waste post-treatment system can be operable to precipitate excessnutrient from the residual biomaterial waste stream liquid, and producea resulting product at the product outlet and the cleaned liquid streamat the liquid outlet.

In such a system, the waste fermentation system 10 can also include asterilization unit 570 having a liquid waste inlet defining the liquidwaste inlet of the waste fermentation system 10 and a liquid wasteoutlet, wherein the sterilization unit 570 can be operable to sterilizethe biomaterial waste stream and produce a sterilized biomaterial wastestream at the liquid waste outlet of the sterilization unit 570.

Another one of the number of sensors of the biomaterial waste processingsystem can be a flow rate sensor 104 ₅ producing a flow rate signalindicative of a flow rate of the biomaterial waste stream entering theliquid waste inlet of the sterilization unit 570. A controller can beconfigured to control the flow rate of the biomaterial waste streamentering the liquid waste inlet of the sterilization unit 570 betweenupper and lower flow rate thresholds.

The sterilization unit 570 can further be fluidly coupled to an inlet ofa sterilization loop 630, and a pre-sterilization heat exchanger HX2having a fluid passageway having a temperature-controlled fluid passingtherethrough. The pre-sterilization heat exchanger HX2 can be configuredto control the temperature of the biomaterial waste stream to a targetsterilization temperature as a function of the temperature of thetemperature-controlled fluid. For example, the waste fermentation system10 can further include a steam unit 572 supplying thetemperature-controlled fluid to the pre-sterilization heat exchanger HX2in the form of steam.

The sterilization unit 570 can further include a post-sterilization heatexchanger HX1 configured to transfer heat from the sterilizedbiomaterial waste stream exiting the sterilization unit 570 to thebiomaterial waste stream entering the pre-sterilization heat exchanger.

The waste fermentation system 10 can further include a fermentation unit580 having a sterilized waste stream inlet fluidly coupled to the wastestream outlet of the sterilization unit 570, a microorganism outletdefining the product outlet of the waste fermentation system 10 and aresidual biomaterial waste stream liquid outlet fluidly coupled to theliquid outlet of the waste fermentation system 10. Such a fermentationunit 580 can be configured to aerobically ferment the sterilizedbiomaterial waste stream to produce the microorganism (i.e., afermenting organism) and the residual biomaterial waste stream liquid.The fermentation unit 580 can further include a seed inlet SD1 and SD2for receiving a microorganism, wherein contact of the microorganism withthe sterilized biomaterial waste stream within the fermentation unit 580can commence fermentation of the sterilized biomaterial waste stream.The waste fermentation system 10 can further include a cooling unitconfigured to control the temperature of the sterilized biomaterialwaste stream entering the fermentation unit 580 to a target waste streamtemperature.

In one embodiment, a method of treating a biomaterial waste stream toremove pollutants and to generate a product is provided. The methodcomprises the steps of injecting the biomaterial waste stream into afirst fermentation unit 580, contacting the biomaterial waste streamwith a first microorganism in the first fermentation unit 580,subjecting the biomaterial waste stream in the first fermentation unit580 to conditions conducive to aerobic fermentation of the biomaterialwaste stream, removing at least a portion of the biomaterial wastestream from the first fermentation unit 580, injecting the at least aportion of the biomaterial waste stream into a second fermentation unit580 in fluid communication with the first fermentation unit 580,contacting the biomaterial waste stream with a second microorganism inthe second fermentation unit 580, and subjecting the biomaterial wastestream in the second fermentation unit 580 to conditions conducive toaerobic fermentation of the biomaterial waste stream.

In this embodiment, the first and second microorganism can be the samespecies of microorganism or the first and second microorganism can bedifferent species of microorganism. Further, in this embodiment, thefirst microorganism in the first fermentation unit can be selected fromthe group consisting of a non-flocculated organism, a naturallyflocculating organism, and an artificially flocculating organism, andthe second microorganism in the second fermentation unit can be selectedfrom the group consisting of a non-flocculated organism, a naturallyflocculating organism, and an artificially flocculating organism withthe proviso that the first and the second microorganism cannot both benon-flocculating.

The system and fermentation method described above can be used toproduce a valuable product. The microorganism removed from thefermentation unit 580, can be used, for example, as an animal feedadditive, a feed supplement, a fertilizer, a fertilizer ingredient, or asoil conditioner.

Illustrative Embodiments of a Flocculation Method and FlocculatedOrganism

The present invention is based, in part, on the discovery of a methoduseful for the catalyzed flocculation of microorganisms. The methodcomprises contacting the microorganisms with a cationic flocculatingagent, contacting the microorganisms with an anionic flocculating agent,and flocculating the microorganisms. The rate and the extent offlocculation of microorganisms that are naturally flocculating, or arenot naturally flocculating, can be controlled using this method. Thus,this method results in the catalyzed flocculation of microorganismswhereby the rate and extent of flocculation of naturally ornon-naturally flocculating microorganisms can be controlled. The methodcan be used to separate naturally flocculating or non-flocculatingmicroorganisms from bulk fluids by sedimentation, for example, whenultrafiltration or ultracentrifugation is impractical.

The microorganisms that can be flocculated using this method include,for example, bacteria, yeast, fungi, mycoplasma, and the like. Yeastspecies that can be used in the presently described method include suchyeast species as Saccharomyces species, Zygosaccharomyces species,Candida species, Hansenula species, Kluyveromyces species, Debaromycesspecies, Nadsonia species, Lipomyces species, Torulopsis species,Kloeckera species, Pichia species, Yersinia species, Schizosaccharomycesspecies, Trigonopsis species, Brettanomyces species, Cryptococcusspecies, Trichosporon species, Aureobasidium species, Phaffia species,Rhodotorula species, Yarrowia species, or Schwanniomyces species, or anyother yeast species that is capable of being flocculated using themethod described herein. Various yeast species are described in N. J. W.Kreger-van Rij, Biology of Yeasts, Vol. 1, Chap. 2, A. H. Rose and J. S.Harrison, Eds. Academic Press, London, 1987, incorporated herein byreference.

Bacterial species that can be flocculated using the presently describedmethod include gram positive and gram negative bacteria and include, forexample, Proteus species, Klebsiella species, Providencia species,Yersinia species, Erwinia species, Enterobacter species, Salmonellaspecies, Serratia species, Aerobacter species, Escherichia species,Pseudomonas species, Shigella species, Vibrio species, Aeromonasspecies, Campylobacter species, Streptococcus species, Staphylococcusspecies, Lactobacillus species, Micrococcus species, Moraxella species,Bacillus species, Bordetella species, Enterococcus species,Propionibacterium species, Streptomyces species, Clostridium species,Corynebacterium species, Eberthella species, Micrococcus species,Mycobacterium species, Neisseria species, Haemophilus species,Bacteroides species, Listeria species, Erysipelothrix species,Acinetobacter species, Brucella species, Pasteurella species, Vibriospecies, Flavobacterium species, Fusobacterium species, Streptobacillusspecies, Calymmatobacterium species, Legionella species, Treponemaspecies, Borrelia species, Leptospira species, Actinomyces species,Nocardia species, Rickettsia species, and any other bacterial speciesthat is capable of being flocculated according to the method describedherein.

Examples of fungi that can be flocculated using the presently describedmethod include, but are not limited to, fungi that grow as molds or areyeastlike, including, for example, fungi that cause diseases such asringworm, histoplasmosis, blastomycosis, aspergillosis, cryptococcosis,sporotrichosis, coccidioidomycosis, paracoccidioidomycosis,mucormycosis, chromoblastomycosis, dermatophytosis, protothecosis,fusariosis, pityriasis, mycetoma, paracoccidioidomycosis,phaeohyphomycosis, pseudallescheriasis, sporotrichosis, trichosporosis,pneumocystis infection, and candidiasis.

In one embodiment, the microorganisms flocculated in accordance with thepresently described method are fermenting organisms. In one embodiment,the microorganisms flocculated in accordance with the presentlydescribed method can be thermophilic microorganisms. In anotherembodiment, the microorganisms can be microorganisms that are notthermophilic. The microorganisms can be naturally present in the samplein which the microorganisms are flocculated (e.g., bulk fluids) or themicroorganisms can be flocculated and then inoculated into a sample(e.g., bulk fluids) in which the flocculated microorganisms areseparated from the bulk fluids by sedimentation. The microorganisms canbe partially or completely flocculated and the microorganisms can benon-flocculating or naturally flocculating.

In one embodiment, the microorganisms are microorganisms that have beenpreviously isolated to obtain a single species of microorganism. Inanother embodiment, the microorganisms have not been previouslyisolated. In another embodiment, the microorganisms comprise a mixtureof species of microorganisms, and that mixture of microorganisms can bea mixture of isolated microorganisms or can be a mixture ofmicroorganisms that are naturally present in a sample. In yet anotherembodiment, the microorganisms can be flocculated and then inoculatedinto a sample. Alternatively, the microorganisms can be flocculated in asample, or can be flocculated after removal from a sample.

In one embodiment, a method of sedimenting microorganisms is provided.The method can be used to separate the flocculated microorganisms frombulk fluids. The method comprises the steps of contacting themicroorganisms with a cationic flocculating agent, contacting themicroorganisms with an anionic flocculating agent, flocculating themicroorganisms, and sedimenting the microorganisms, such as by, forexample, allowing the flocculated microorganisms to settle. In oneembodiment, the microorganisms can be flocculated, inoculated into bulkfluids, and then separated from the bulk fluids by sedimentation. Inanother embodiment, the microorganisms can be flocculated in the bulkfluids, and then separated from the bulk fluids by sedimentation.

Cationic flocculating agents useful in the compositions and methodsdescribed herein are positively charged molecules or molecules capableof carrying one or more positive charges under predetermined conditions,and include but are not limited to salt counterions, such as metalcations and salts thereof, including iron, chromium, cobalt, nickel,copper, manganese, and the like, and including multivalent metalcations, such as divalent and trivalent metal cations, and the like;small molecules such as di-, tri-, and tetraamines; polymeric materials,such as polyamines and salts thereof; and combinations thereof. Anionicflocculating agents useful in the compositions and processes describedherein are negatively charged molecules or molecules capable of carryingone or more negative charges under predetermined conditions, and includebut are not limited to salt counterions such as carbonates, sulfates,phosphates, and the like; small molecules such as di-, tri-, andtetracarboxylic acids, di-, tri-, and tetrasulfinic and sulfonic acids,di-, tri-, and tetraphosphinic and phosphonic acids; polymeric materialsthat carry or can carry a negative charge, such as polyols, polythiols,polyacids, polysulfonates, polycarboxylates, polyphosphonates, and saltsthereof; and combinations thereof.

In one aspect, the metal cations have a “2+” or a “3+” charge.

In one embodiment, a flocculating agent of a cationic type can be usedin combination with a flocculating agent of an anionic type to catalyzeflocculation artificially. Any combination of cationic and anionicflocculating agents may be used to catalyze flocculation. It isappreciated that combinations of cationic and anionic flocculatingagents that form higher levels of aggregated solids with microorganismsare more easily separated from the bulk fluids. Illustratively, thecombinations of cationic and anionic flocculating agents used in thecompositions and methods described herein include at least one agentthat is a polymeric material.

Illustratively, the flocculating agent of the cationic type can beferrous chloride, ferrous sulphate, ferric chloride, ferric sulphate,chlorinated ferric sulphate, aluminium sulphates, chlorinated basicaluminum sulphates, magnesium chloride, magnesium sulphate, and thelike, and combinations thereof. Illustratively, the flocculating agentof the anionic type can be anionic polyacrylamides, polyacrylates,polymethacrylates, polycarboxylates, polysaccharides (e.g., xanthan gum,partially hydrolyzed guar gums, gum Arabic, or alginates and partiallyhydrolyzed alginates), chitosan, celluloses, and the like, andcombinations thereof. A mixture of flocculating agents of the cationicand/or the anionic type can also be used. Any synthetic flocculatingagent can also be used.

Without being bound by theory, it is believed that flocculation isaccomplished by the interaction and aggregation of alternating anionicflocculating agents, cationic flocculating agents, and microorganisms.It is further believed that microorganisms generally present a surfacehaving an overall negative charge. In one illustrative embodiment,flocculation including the following is described:

where B^(r−) represents an anionic flocculating agent and A^(q+)represents a cationic flocculating agent. In the above embodiment, theanionic flocculating agent is in the form of a polymeric compound. It isto be understood that other anionic and cationic flocculating agents maybe involved in the alternating arrangement forming more complexaggregates.

In another illustrative embodiment, flocculation including the followingis described:

where A^(q+) represents a first cationic flocculating agent, B^(r−)represents an anionic flocculating agent, and C^(s+) represents a secondcationic flocculating agent. In the above embodiment, the cationicflocculating agent is in the form of a polymeric compound.

In one aspect, where the anionic flocculating agent is a polymericcompound, the affinity of the anionic flocculating agent for thecationic flocculating agent is selected to be about competitive with theaffinity of the cell for the cationic flocculating agent. It isappreciated that the relative affinities may be adjusted or modified bythe conditions, such as by choice of solvent, ionic strength, pH,temperature, and the like.

In another aspect, the relative charge density on polymeric anionic andcationic flocculating agents is low. It is appreciated that low chargedensity may increase the aggregation of microorganisms by decreasing theamount of self-aggregation. In one aspect, the charges are separated onthe polymeric anionic and/or cationic flocculating agents by more thanabout 50 or more than about 100 atoms. In variations where the entropyof the polymer is restricted, such as by the presence of branching,multiple bonds, and/or cyclic substructures, the charges are separatedon the polymeric anionic and/or cationic flocculating agents by morethan about 30 or more than about 40 atoms.

In another aspect, the relatively low charge density is understood interms of molecular weight. Illustratively, the polymeric anionic andcationic flocculating agents include compounds having one charge perabout 1000 or about 2000 atomic units. In variations where the entropyof the polymer is restricted, such as by the presence of branching,multiple bonds, and/or cyclic substructures, there is one charge perabout 400 or about 600 atomic units.

Polymeric anionic and cationic flocculating agents include naturallyoccurring polymers, such as polysaccharides, xanthan gum, partiallyhydrolyzed guar gums or gum Arabic, alginates and partially hydrolyzedalginates, chitosan, celluloses, hemicelluloses, polypeptides andproteins, other emulsifying agents, and the like, and syntheticpolymers, such as polyacrylamides, polyacrylates, polymethacrylates,polycarboxylates, partially hydrolyzed polyacrylamides, polyacrylates,polymethacrylates, and polycarboxylates, and the like. In oneillustrative aspect, the polymeric anionic and cationic flocculatingagents are food grade, such as xanthan gum and other emulsifying agents.

In one embodiment, the microorganism is artificially flocculated usingferric chloride and xanthan gum. In one embodiment, the concentration ofthe flocculating agent of the cationic type can range from about 0.01ppm to about 300 ppm, and the concentration of the flocculating agent ofthe anionic type can range from about 0.001 g/L to about 10 g/L.

The bulk fluids can be of any volume. For example, the bulk fluids canrange from a volume of about 0.1 ml to about 1000 liters. In otherembodiments, the volume of the bulk fluids can be less than 0.1 ml orgreater than 1000 liters. In one embodiment, the bulk fluids can be anyfluids in which a microorganism is typically found. For example, thebulk fluids can be a biomaterial waste stream, a body fluid, a culturemedium for microorganisms, or any fluid used to process microorganisms,such as fluids used for processing microorganisms in a researchlaboratory, or any other fluid in which microorganisms are typicallypresent. In another embodiment, the microorganisms can be inoculatedinto the bulk fluids. The rate and extent of flocculation can becontrolled by varying such conditions as pH, ion concentration (e.g.,magnesium concentration), concentration of the cationic flocculatingagent (e.g., iron), and by addition of organic molecules that bind todivalent ions (e.g., xylitol). Variation in such conditions can be usedto flocculate a particular species of microorganism in a mixture if thatmicroorganism flocculates under the particular conditions used and othermicroorganisms do not (see Examples 15-19). Thus, the method describedherein can be used to separate a particular species of microorganismfrom another species of microorganism in a mixture of microorganisms.Accordingly, the method may be useful, for example, for separatingmicroorganisms in a sample of body fluid for examination of theseparated or isolated microorganisms employing techniques useful fordiagnosis of disease states.

In one embodiment, the microorganisms flocculated by the methoddescribed herein are useful for treating a biomaterial waste stream toremove pollutants in the biomaterial waste stream by converting thepollutants to a valuable product. In this embodiment, the microorganismcan be a fermenting organism. In one embodiment a biomaterial wastestream is subjected to oxidative fermentation in the presence ofmicroorganisms flocculated by the method described herein (i.e., afermenting organism) to convert the pollutants in the biomaterial wastestream to a valuable product. Accordingly, at least a portion of thepollutants (e.g., phosphorous, nitrogen, and potassium) is removed fromthe biomaterial waste stream and incorporated into the valuable product,for example, the microorganism (i.e., a fermenting organism), reducingenvironmental pollution. Fermentation of a biomaterial waste streamusing flocculated microoganisms results in the production of a valuableprotein product (e.g., a microorganism such as a yeast) that can beused, for example, as an animal feed additive, a feed supplement, afertilizer, a fertilizer ingredient, or a soil conditioner.

Exemplary biomaterial waste streams that can be treated withmicroorganisms flocculated by the presently described method include,but are not limited to, manure, cellulosistic solid waste, whey brothfrom cheese production or biomaterial waste streams from otherfoodstuffs, broth remediation from alcohol or yeast production, tannerywaste, slaughterhouse waste, tallow waste from rendering processes,waste derived from plants, and land fill waste. The waste derived fromplants can be, for example, waste from hay, leaves, weeds, or wood andcan be, for example, yard waste, landscaping waste, agricultural cropwaste, forest waste, pasture waste, or grassland waste. The wastederived from foodstuffs can be fruit and vegetable processing waste,fish and meat processing wastes, bakery product waste, and the like. Inembodiments where the waste is manure, the manure can be from an animalsuch as a human, a bovine animal, an equine animal, an ovine animal, aporcine animal, or poultry. In one embodiment the biomaterial wastestream is a variable and dilute biomaterial waste stream derived fromanimal manure or human waste. In general, any organic waste containingproteins, simple or complex carbohydrates, or lipids, or a combinationthereof, can be treated with the microorganisms flocculated according tothe method described herein. The use of microorganisms (i.e., afermenting organism) flocculated according the presently describedmethod allows for the extraction of nutrients from dilute biomaterialwaste streams using, for example, dilution protocol fermentation.

In embodiments where the flocculated microorganism is used to treat abiomaterial waste stream, the microorganism (i.e., a fermentingorganism) can be any of those described above. In one embodiment, theflocculated microorganism that contacts the biomaterial waste stream canbe a thermophilic microorganism. In another embodiment, themicroorganism can be a microorganism that is not thermophilic. Themicroorganism (i.e., a fermenting organism) can be naturally present inthe biomaterial waste stream and can be flocculated in the biomaterialwaste stream, or the biomaterial waste stream can be inoculated with theflocculated microorganism. The microorganism can be partially orcompletely flocculated and the microorganism can be non-flocculating ornaturally flocculating.

In embodiments where the flocculated microorganism is used to treat abiomaterial waste stream (i.e., a fermenting organism), a flocculatingagent of a cationic type can be used in combination with a flocculatingagent of an anionic type to induce flocculation artificially asdescribed above. The flocculating agent of the cationic type can be anyof those described above. For example, the flocculating agent of thecationic type can be selected from the group including ferrous chloride,ferrous sulphate, ferric chloride, ferric sulphate, chlorinated ferricsulphate, aluminium sulphates, chlorinated basic aluminum sulphates,magnesium chloride, magnesium sulphate, and the like. The flocculatingagent of the anionic type can be any of those described above. Forexample, the flocculating agent of the anionic type can be selected fromthe group including an anionic polyacrylamide, a polyacrylate, apolymethacrylate, a polycarboxylate, a polysaccharide (e.g., xanthangum, partially hydrolyzed guar gums or gum Arabic, or alginates orpartially hydrolyzed alginates), chitosan, cellulose, and the like. Amixture of flocculating agents of the cationic and/or the anionic typecan also be used. In one embodiment, the microorganism is artificiallyflocculated using ferric chloride and xanthan gum.

In one embodiment, the microorganism (i.e., a fermenting organism)flocculated according to the method described herein utilizes thepollutants in the biomaterial waste stream (e.g., potassium, nitrogen,and phosphorus) as nutrients, and the flocculated microorganismsproduced during fermentation of the biomaterial waste stream can be usedas an animal feed, an animal feed supplement, a fertilizer, a fertilizeringredient, or a soil conditioner.

The flocculated microorganism can be preserved using any method known inthe art for preventing degradation of a microorganism and/or its proteincomponents. For example, the microorganism can be pasteurized or themicroorganism can be refrigerated after removing the microorganism fromthe fermentation unit. The microorganism can be used as a valuableproduct in the form of, for example, a paste, or another aqueousmixture, or a dry powder. Alternatively, the wet product resulting fromthe fermentation can be used without further processing.

In one embodiment, a flocculated microorganism prepared according to thepresently described method for flocculation of microorganisms isprovided. In another embodiment, a feed composition is providedcomprising an animal feed blend and a flocculated microorganism preparedin accordance with the presently described method. In still anotherembodiment an animal feed supplement comprising a flocculatedmicroorganism prepared in accordance with the presently described methodis provided.

In one embodiment, the flocculated microorganism is added to an animalfeed blend to form a feed composition. Any animal feed blend known inthe art can be used such as rapeseed meal, cottonseed meal, soybeanmeal, and cornmeal. Optional ingredients of the animal feed blendinclude sugars and complex carbohydrates such as both water-soluble andwater-insoluble monosaccharides, disaccharides and polysaccharides.Optional amino acid ingredients that may be added to the feed blend arearginine, histidine, isoleucine, leucine, lysine, methionine,phenylalanine, threonine, tryptophan, valine, tyrosine ethyl HCl,alanine, aspartic acid, sodium glutamate, glycine, proline, serine,cysteine ethyl HCl, and analogs, and salts thereof. Vitamins that canoptionally be added are thiamine HCl, riboflavin, pyridoxine HCl,niacin, niacinamide, inositol, choline chloride, calcium pantothenate,biotin, folic acid, ascorbic acid, and vitamins A, B, K, D, E, and thelike. Protein ingredients can also be added and include protein obtainedfrom meat meal, liquid or powdered egg, and the like. Any medicamentingredients known in the art can also be added to the animal feed blendsuch as antibiotics.

In one embodiment, the feed composition is supplemented with theflocculated microorganisms in amounts of about 0.025% to about 1% byweight of the feed composition. In another embodiment the feedcomposition is supplemented with the flocculated microorganisms inamounts of about 0.025% to about 2%. In yet another embodiment the feedcomposition is supplemented with the flocculated microorganisms inamounts of about 0.025% to about 5% by weight of the feed composition.In another embodiment the feed composition is supplemented with theflocculated microorganisms in amounts of about 0.025% to about 10% byweight of the feed composition. In each of these embodiments it is to beunderstood that the percentage of the flocculated microorganisms byweight of the feed composition refers to the final feed composition(i.e., the feed composition as a final mixture) containing the animalfeed blend, the flocculated microorganisms, and any other optionallyadded ingredients.

An animal feed supplement comprising flocculated microorganisms is alsoprovided. The animal feed supplement can be a wet or a dry product andthe animal feed supplement can be processed so that it is in the form ofa paste, an aqueous mixture, a dry powder, or in any other suitableform. The animal feed supplement can contain any of the components ofthe animal feed blend described above, and the animal feed supplementcan be mixed with an animal feed blend to form a final mixture (i.e., afeed composition as a final mixture). The amounts of flocculatedmicroorganisms by weight of the feed composition can be any of thosedescribed above.

EXAMPLE 8 Catalysis of Flocculation of Pichia Stipitis

Xanthan gum (0.25%; Sigma, St. Louis, Mo.) and ferric chloride solution(0.5%) were prepared. Pichia stipitis was grown in YPD medium (1% yeastextract, 2% peptone, and 2% glucose). A final yeast suspension of 4 g/Lon a dry weight basis was used. Yeast suspension (40 ml) was poured into50 ml plastic tubes, and 2 ml of 0.25% xanthan gum solution was added toachieve a final xanthan gum concentration in the yeast suspension of0.125 g/L. Various amounts of ferric chloride solution were added toobtain an iron concentration of 20 to 90 ppm. The mixture was thengently shaken for 30 seconds, and the flocs of yeast were allowed tosettle. After settling for 4 minutes, samples were taken from the top ofthe plastic tube and the samples contained a portion of the supernatant.Cell counts for the samples were determined by using a hemocytometer.

As shown in FIG. 31, iron caused a partial to a complete flocculationdepending on the concentration of iron present (e.g., 70 ppm or greaterfor complete flocculation). The results depicted in FIG. 31 show notonly that flocculation can be catalyzed, but that partial flocculationcan be achieved by limiting the concentration of ferric chloride added.As the data in FIG. 31 show, at least a ten-fold variation insupernatant cell concentration can be obtained by varying the ironconcentration.

Accordingly, catalyzed flocculation provides control of flocculationthat is surprisingly better than that accomplished by using a naturallyflocculating species of microorganism. The ratio of flocculated tounflocculated yeast cells using a naturally flocculating species, istypically about 2-3:1. When flocculation is catalyzed as shown in FIG.31, the percentage of flocculated cells ranges from about 0 to about100% depending on the ferric chloride concentration used.

EXAMPLE 9 Catalysis of Flocculation of Pinhia Stipitis

Xanthan gum (0.25%; Sigma St. Louis, Mo.) and ferric chloride solution(0.145%) were prepared. Pichia stipitis was grown in YPD medium (1%yeast extract, 2% peptone, and 2% glucose). A final yeast suspension of4 g/L on a dry weight basis was used. Yeast suspension (10 ml) waspoured into 15 ml plastic tubes, and various amounts of the xanthan gumand ferric chloride solutions were added to obtain a xanthan gumconcentration of 0.00625 to 0.1 g/L, and an iron concentration of 20 to90 ppm. The mixture was then gently shaken for 30 seconds, and the flocsof yeast were allowed to settle. After settling for 3 minutes, samplesof the supernatant were taken from each tube. For each sample, opticaldensity (O.D.) at 600 nm was measured (see FIG. 32 and Table 8), and theiron concentration was determined by using an iron diagnostic kit(Sigma, St. Louis, Mo.) based on the Persijn method (see FIG. 33 andTable 9). The results depicted in FIG. 32 show that flocculation can becatalyzed, that the concentration of iron that achieves completeflocculation is dependent on the concentration of xanthan gum, and thatflocculation can be controlled (i.e., partial flocculation can beachieved) by varying the concentration of iron. Similar results wereobtained using ferric sulfate in place of ferric chloride. With no yeastpresent, ferric ion and xanthan gum do not precipitate, and xanthan gumdoes not precipitate in the absence of ferric ion. Flocculation ofSaccharomyces cerevisiae and Candida utilis were also catalyzed andcontrolled using this method. TABLE 8 OD at 600 nm Iron (ppm) 0.1 g/Lxanthan 0.05 gL xanthan 0.025 g/L xanthan 0 4.96 4.99 5.02 5 4.41 4.264.67 10 3.47 3.26 2.83 15 2.37 1.08 0.227 20 0.417 0.074 0.101 25 0.0950.05 0.077 30 0.066 0.05 0.077 35 0.066 0.05 0.077

TABLE 9 OD at 600 nm Iron (ppm) 0.0125 g/L xanthan 0.00625 gL xanthan 05.4 5.37 2 5.29 5.44 4 4.95 5.32 6 4.6 4.86 8 3.99 4.53 10 2.94 3.82 121.67 2.63 14 0.744 1.45 16 0.134 0.312 18 0.134 0.215

EXAMPLE 10 Catalysis of Flocculation of Saccharomyces Cerevisiae

Xanthan gum (0.25%; Sigma St. Louis, Mo.), 0.145% ferric chloride, 0.56%magnesium sulphate, and 5% sodium chloride solutions were prepared.Saccharomyces cerevisiae was grown in YPD medium (1% yeast extract, 2%peptone, and 2% glucose). A final yeast suspension of 4 g/L on a dryweight basis was prepared at its natural pH of 4.8. Assays wereperformed to test the effects of magnesium, pH, and sodium chloride onflocculation.

In the first assay, 10 ml of yeast suspension was poured into 15 mlplastic tubes. Xanthan gum was added to obtain a final concentration of0.025 g/L. Magnesium sulphate was added to each tube to obtain a finalmagnesium concentration of 0.5 g/L. Varying amounts of ferric chloridesolution were added to obtain an iron concentration of 0 to 35 ppm.

In the second assay, the pH of the yeast suspension was adjusted to 7.11by adding 4N sodium hydroxide. Yeast suspension (10 ml) was poured into15 ml plastic tubes. Xanthan gum was added to achieve a finalconcentration of 0.025 g/L. Varying amounts of ferric chloride solutionwere added to obtain an iron concentration of 0 to 30 ppm.

In the third assay, 10 ml of yeast suspension was poured into 15 mlplastic tubes. Xanthan gum was added to achieve a final concentration of0.025 g/L. Sodium chloride was added to each tube to obtain a finalconcentration of 2.5 g/L, and varying amounts of ferric chloridesolution were added to obtain an iron concentration of 0 to 20 ppm. Acontrol assay was also included in which 10 ml of yeast suspension waspoured into 15 ml plastic tubes and xanthan gum was added to achieve afinal concentration of 0.025 g/L. Varying amounts of ferric chloridesolution were added to obtain an iron concentration of 0 to 15 ppm. Inall four assays, the flocs of yeast were allowed to settle for 2minutes, and samples were taken from the supernatant in each tube. Foreach sample, optical density (O.D.) at 600 nm was measured (see FIG. 34and Table 10), and the iron concentration was determined by using aniron diagnostic kit (Sigma, St. Louis, Mo.) based on the Persijn method(see FIG. 35 and Table 11).

Magnesium ion is expected to cause interference with ferric ion forbinding to the complex containing yeast and xanthan gum. However, theresults depicted in FIGS. 34 and 35 show that magnesium ion prevents thebinding of excess ferric ion to the complex, but does not interfere withflocculation because flocculation proceeds in the presence of magnesiumion (see FIG. 34), but iron in the supernatant is increased in thepresence of magnesium ion. Competing sodium ion and increased pH (i.e.,a pH of about 7) have little effect. TABLE 10 OD at OD at pH = 4.8 OD atpH = 4.8 600 nm OD at pH = 4.8 600 nm Iron 600 nm Iron 0.5 g/L Iron 600nm Iron 2.5 g/L (ppm) Control (ppm) Mg (ppm) pH = 7.11 (ppm) NaCl 2 4.750 4.31 0 4.54 0 4.69 4 4.76 5 4.32 5 4.39 5 4.56 6 3.82 10 2.95 10 3.939 2.32 7 3.27 12 2.2 15 2.95 12 1.37 8 2.38 15 1.29 20 1.14 15 0.497 91.61 20 0.91 25 0.273 18 0.322 10 1.39 25 0.76 30 0.032 20 0.184 12 0.5130 0.6 15 0.018 35 0.62

TABLE 11 Iron in the Iron in the Iron in the supernatant Iron in thesupernatant pH = 4.8 supernatant pH = 4.8 (ppm) supernatant pH = 4.8(ppm) Iron (ppm) Iron 0.5 g/L Iron (ppm) Iron 2.5 g/L (ppm) Control(ppm) Mg (ppm) pH = 7.11 (ppm) NaCl 2 1.5 0 0 0 0.8 0 0.2 4 2.6 5 3.3 52.8 5 2.9 6 2.8 10 4.2 10 5 9 3.4 7 2.8 12 4 15 3.5 12 3.4 8 2.5 15 4.620 2.4 15 4.4 9 2.5 20 5.6 25 1.3 18 6 10 2.6 25 7.4 30 2 20 7.4 12 3 308.7 15 4.2 35 9

EXAMPLE 11 Catalysis of Flocculation of Yeast Resists Dilution

Saccharomyces cerevisiae, Pichia stipitis, and Candida utilis were usedin the experiment shown in FIG. 36. All yeast types were grown in YPDmedium. Yeast suspensions of approximately 4 g/L on a dry weight basiswere prepared. Yeast suspensions of 10 ml each were placed in 15 mltubes and 0.025 g/L xanthan gum and 15 ppm of iron (from ferricchloride) were added. Flocs of yeast were allowed to settle. After 3minutes, 3 ml was taken from the supernatant, and the sample wasreplenished with 3 ml of distilled water. This dilution process wasrepeated as many times as necessary. For each sample, the opticaldensity at 600 nm was measured to calculate the percentage of yeast inthe flocculating form. The results depicted in FIG. 36 show that yeastflocculated with xanthan gum and ferric ion forms a stable complex thatresists “wash-out” by dilution which is relevant to dilution protocolfermentation in which dilute substrates are used. The low concentrationof xanthan gum (0.0025%) binds to yeast and resists washing underconditions of at least 100% dilution.

EXAMPLE 12 Settling Rate of Yeast after Catalyzed Flocculation

Saccharomyces cerevisiae, Kluyveromyces lactis, Pichia stipitis, andCandida utilis were used in the experiment shown in FIG. 37. All yeastwere grown in YPD medium. Yeast suspensions of approximately 4 g/L on adry weight basis were prepared. A 100 ml volume of yeast suspension with0.025 g/L xanthan gum and 15 ppm iron from ferric chloride was pouredinto a 100 ml cylinder. The depth of the settled yeast flocs wasmeasured against time to calculate the average settling rate offlocculated yeast (see FIG. 37). As shown in FIG. 37, the settling rateof yeast after flocculation is at least 0.1 inch/minute (0.254centimeter/minute). In comparison, the settling rate of unflocculatedyeast is about 0.008 inch/minute (0.020 centimeter/minute).

EXAMPLE 13 Effect of pH on the Catalysis of Flocculation ofSaccharomyces Cerevisiae

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.) and 0.145% ferricchloride solutions were prepared. Saccharomyces cerevisiae was grown inYPD medium (1% yeast extract, 2% peptone, and 2% glucose). The yeastwere harvested by centrifugation and were resuspended in deionizedwater. Final yeast suspensions of 4 g/L dry weight density were used.The pH's of the yeast suspensions were adjusted to pH 1, 3, 5, 7, 9, and11 by adding appropriate amounts of 10% sulfuric acid and 10% sodiumhydroxide. The yeast suspensions (10 ml) were poured into 15 ml tubes.Xanthan gum solution was added to obtain a xanthan gum concentration of0.025 g/L, and ferric chloride solution was added to obtain an ironconcentration of 5 ppm, 10 ppm, or 15 ppm. The suspensions were mixed,settled for 3 minutes, and samples were taken from each tube from thesupernatant. For each sample, optical density (O.D.) at 600 nm wasmeasured, and the percentage of flocculated yeast was calculated (seeFIG. 38). As shown in FIG. 38, variation in pH affects the catalysis offlocculation of yeast.

EXAMPLE 14 Effect of pH and Xylitol on the Catalysis of Flocculation ofSaccharomyces Cerevisiae

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.), 20% xylitol (Sigma, St.Louis, Mo.) and 0.145% ferric chloride solutions were prepared.Saccharomyces cerevisiae was grown in YPD medium (1% yeast extract, 2%peptone, and 2% glucose). The yeast were harvested by centrifugation andresuspended in deionized water. Final yeast suspensions of 4 g/L dryweight density were used. The pH's of the yeast suspensions wereadjusted to 1, 3, 5, 7, 9, and 11 by adding appropriate amounts of 10%sulfuric acid and 10% sodium hydroxide. The yeast suspensions (10 ml)were poured into 15 ml tubes. Xanthan gum solution was added to eachsuspension to obtain a xanthan gum concentration of 0.025 g/L. Ferricchloride solution was added to obtain an iron concentration of 5 ppm, 10ppm, or 15 ppm and xylitol solution was added to obtain xylitolconcentrations of 2 g/L, 4 g/L, or 6 g/L. The suspensions were mixed,settled for 3 minutes, and samples were taken from each tube from thesupernatant. For each sample, optical density (O.D.) at 600 nm wasmeasured, and the percentage of flocculated yeast was calculated (seeFIG. 39). The results presented in FIG. 39 show that xylitol which bindsdivalent ions, blocks the recovery of flocculation that occurs at highpH (see FIG. 38) and increasing iron concentration tends to reverse thiseffect (see FIG. 39).

EXAMPLE 15 Catalysis of Flocculation of Gram Negative Bacteria

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.) and 0.145% ferricchloride solutions were prepared. E. coli (gram negative bacteria) weregrown in YPD medium (1% yeast extract, 2% peptone, and 2% glucose) underlimited aeration. The E. coli were harvested by centrifugation andresuspended in deionized water. A final E. coli suspension of 4 g/L dryweight density was used. The pH's of E. coli suspensions were adjustedto 5 and 9 by adding appropriate amounts of 10% sulfuric acid and 10%sodium hydroxide. Aliquots of E. coli suspension were poured into 15 mltubes. Xanthan gum solution was added to each tube to obtain a xanthangum concentration of 0.025 g/L, and various amounts of ferric chloridesolution were added to obtain iron concentrations of from 5 to 30 ppm.The solutions were mixed, settled for 3 minutes, and samples were takenfrom each tube from the supernatant. For each sample, optical density(O.D.) at 600 nm was measured, and the percentage of flocculated E. coliwas calculated (see FIG. 40). The results depicted in FIG. 40 show thatthe flocculation of E. coli can be catalyzed and controlled and that theiron concentration for half-maximal flocculation is about 12 ppm at pH 5and about 15 ppm at pH 9.

EXAMPLE 16 Catalysis of Flocculation of Gram Positive Bacteria

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.) and 0.145% ferricchloride solutions were prepared. Bacillus sp. (gram positive bacteria)was grown in YPD medium (1% yeast extract, 2% peptone, and 2% glucose)under limited aeration. Bacillus sp. was harvested by centrifugation andresuspended in deionized water. A final Bacillus sp. suspension of 4 g/Ldry weight density was used. The pH's of Bacillus sp. suspensions wereadjusted to 5 and 9 by adding appropriate amounts of 10% sulfuric acidand 10% sodium hydroxide. Bacillus sp. suspensions were poured into 15ml tubes. Xanthan gum solution was added to each tube to obtain axanthan gum concentration of 0.025 g/L, and various amount of ferricchloride solution was added to obtain iron concentrations of from 0.2 to5 ppm. The solutions were mixed, settled for 3 minutes, and samples weretaken from each tube from the supernatant. For each sample, opticaldensity (O.D.) at 600 nm was measured, and the percentage of flocculatedBacillus sp. was calculated. The results depicted in FIG. 41 show thatthe flocculation of Bacillus sp. can be catalyzed and controlled. Incontrast to E. coli, the iron concentration for half-maximalflocculation is about 0.2 ppm at pH 5 and about 2 ppm at pH 9.

EXAMPLE 17 Catalysis of Flocculation of Gram Negative Bacteria

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.) and 0.145% ferricchloride solutions were prepared. E. coli (gram negative bacteria) weregrown in YPD medium (1% yeast extract, 2% peptone, and 2% glucose) underlimited aeration. The E. coli were harvested by centrifugation andresuspended in deionized water. A final E. coli suspension of 4 g/L dryweight density was used. The pH's of E. coli suspensions were adjustedto 3, 5, 7, 9, and 11 by adding appropriate amounts of 10% sulfuric acidand 10% sodium hydroxide. Aliquots (10 ml) of E. coli suspension werepoured into 15 ml tubes. Xanthan gum solution was added to each tube toobtain a xanthan gum concentration of 0.025 g/L, and various amounts offerric chloride solution were added to obtain iron concentrations offrom 5 to 70 ppm. The solutions were mixed, settled for 3 minutes, andsamples were taken from each tube from the supernatant. For each sample,optical density (O.D.) at 600 nm was measured, and the percentage offlocculated E. coli was calculated (see FIG. 40). The results depictedin FIG. 42 show that the flocculation of E. coli can be catalyzed andcontrolled. In comparison to FIG. 43, the iron concentration forhalf-maximal flocculation of E. coli is at least 20 ppm at pH 3, and isabout 2 ppm at pH 4 for Bacillus sp.

EXAMPLE 18 Catalysis of Flocculation of Gram Positive Bacteria

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.) and 0.145% ferricchloride solutions were prepared. Bacillus sp. (gram positive bacteria)was grown in YPD medium (1% yeast extract, 2% peptone, and 2% glucose)under limited aeration. Bacillus sp. was harvested by centrifugation andresuspended in deionized water. A final Bacillus sp. suspension of 4 g/Ldry weight density was used. The pH's of Bacillus sp. suspensions wereadjusted to 4, 5, 7, 9, and 11 by adding appropriate amounts of 10%sulfuric acid and 10% sodium hydroxide. Bacillus sp. suspensions (10 ml)were poured into 15 ml tubes. Xanthan gum solution was added to eachtube to obtain a xanthan gum concentration of 0.025 g/L, and variousamounts of ferric chloride solution were added to obtain ironconcentrations of from 2 to 85 ppm. The solutions were mixed, settledfor 3 minutes, and samples were taken from each tube from thesupernatant. For each sample, optical density (O.D.) at 600 nm wasmeasured, and the percentage of flocculated Bacillus sp. was calculated.The results depicted in FIG. 43 show that the flocculation of Bacillussp. can be catalyzed and controlled. In comparison to FIG. 42, the ironconcentration for half-maximal flocculation of Bacillus sp. is about 2ppm at pH 4 and is at least 20 ppm at pH 3 for E. coli. Thus, much loweriron concentration is needed for flocculation of gram-positive bacteriathan for gram-negative bacteria, especially at low pH. Furthermore, inmixed cultures of gram-positive and negative bacteria, at appropriateiron and xanthan gum concentrations and at an appropriate pH, separationof gram positive and gram negative bacteria can be achieved (see Example19).

EXAMPLE 19 Separation of Gram Negative and Gram Positive Bacteria

Xanthan gum (0.025 g/L; Sigma, St. Louis, Mo.) and 0.145% ferricchloride solutions were prepared. Bacillus sp. (gram positive bacteria)and E. coli (gram negative bacteria) were grown in YPD medium (1% yeastextract, 2% peptone, and 2% glucose) under limited aeration for 18hours. For both types of microorganisms, cells were harvested bycentrifugation and resuspended in deionized water. Final cellsuspensions of 4 g/L dry weight density were used. The pH's of aliquotsof the cell suspensions were adjusted to 4, 5, 7, 9, and 11 by addingappropriate amounts of 10% sulfuric acid and 10% sodium hydroxide.Bacillus sp. and E. coli suspensions (5 ml each) were mixed together in15 ml tubes. Xanthan gum solution was added to each tube to obtain axanthan gum concentration of 0.025 g/L, and ferric chloride solution wasadded to obtain an iron concentration of 10 ppm. The solutions weremixed, settled for 3 minutes, and samples were taken from each tube fromthe supernatant. An appropriate dilution of 101 to 106 was made. A gramstain was performed on the sample that was diluted 1:10. The number ofgram positive and gram negative cells were counted under the microscope,and 0.1 ml samples were spread on Bacto EMB agar plates and Bacto TSAblood agar plates. The plates were incubated at 37° C. for 24 hours.

The gram-stain showed that in the supernatant over 90% of cells weregram negative E. coli (30 gram-positive organisms versus 310 gramnegative organisms per slide). The gram-positive Bacillus sp. causes aβ-hemolytic reaction on TSA blood agar, and does not grow on EMB agar.On EMB agar, E. coli grows colonies with blue-black centers and a greenmetallic sheen. After 24 hours of incubation, the sample with the 1:106dilution had 164 colonies on EMB agar, and no hemolytic reaction wasobserved on TSA blood agar. Thus, under appropriate conditions, gramnegative E. coli can be enriched in the supernatant from the mixedcultures by flocculating most gram positive Bacillus sp.

Illustrative Embodiments of a Process and Apparatus for Removing Solidsfrom Aqueous Solutions

Processes and apparatus are described herein for removing dissolved,undissolved, and/or suspended solids from aqueous solutions. In oneembodiment, processes and apparatus are described herein for removingdissolved, undissolved, or suspended solids from aqueous solutions byprecipitation. In another embodiment, processes and apparatus aredescribed herein for removing dissolved, undissolved, or suspendedsolids from aqueous solutions by crystallization. In another embodiment,processes and apparatus are described herein for removing dissolved,undissolved, or suspended solids from aqueous solutions by aggregation.In another embodiment, processes and apparatus are described herein forremoving other dissolved, undissolved, or suspended solids from aqueoussolutions by absorption and/or adsorption. As used herein, the term“aggregation” will generally refer to each of these processes andvarious combinations of these processes.

The aqueous solutions used in the processes and apparatus describedherein may be derived from any source. In one embodiment, the aqueoussolution is a dilute solution. In another embodiment, the aqueoussolution is provided by or derived from a solution exiting afermentation process, including a fermentation process described herein.It is understood that such a fermentation process may be used to removecertain components from an input stream, such as a biomaterial wastestream derived from animal waste, animal manure, including ruminant,semi-ruminant, swine, and poultry manure, cellulosistic waste, foodprocessing waste, including whey broth from cheese production, brothremediation from alcohol production or yeast production, tannery waste,slaughterhouse waste, tallow waste, including waste from renderingprocesses, used fats and/or cooking oils, landscaping waste, includingwaste derived from plants, paper processing waste, land fill waste, andthe like. The waste derived from animals that may be treated using theprocesses and apparatus described herein can be, for example, fromruminants, including semi, partial, and full ruminants, swine, includinggrowers, beef cattle, dairy cattle, horses, poultry, including layersand broilers, and the like. The waste derived from plants can be, forexample, waste from hay, leaves, weeds, sawdust, or wood and can be, forexample, yard waste, landscaping waste, agricultural crop waste, forestwaste, pasture waste, and/or grassland waste. The waste derived fromfoodstuffs can be fruit and vegetable processing waste, fish and meatprocessing wastes, bakery product waste, waste from cheese productionsuch as whey, used fats and oils, and the like.

In one illustrative embodiment, the processes and apparatus describedherein may be used to remove components from a biomaterial waste streamthat are not removed by a fermentation process. In one aspect, abiomaterial waste stream is fed into a fermentation process, and theresulting fermented biomaterial waste stream is fed into a process orapparatus described herein for removing components from aqueoussolutions. In one variation, the fermented biomaterial waste streamcannot be recycled, and/or discarded or disposed of in some mannerbecause it contains a dissolved, undissolved, or suspended solidpreventing disposal. In another variation, a biomaterial waste stream ora fermented biomaterial waste stream is fed into a process or apparatusdescribed herein for removing components from aqueous solutions, and theresulting treated biomaterial waste stream is cleaned, purified, and/orclarified and may be discarded or disposed of in ordinary disposalstreams, such as a sanitary landfill or as ground water, and/or isrecycled as cleaned, clarified, or purified water into other processesor apparatus, such as processes or apparatus described herein.

Illustratively, dissolved, undissolved, and/or suspended solids orcomponents that may be removed from aqueous solutions using theprocesses and apparatus described herein include metals, cations, andanions, including inorganic anions such as sulfate, phosphate, and thelike. Other dissolved, undissolved, or suspended components that may beremoved using the processes and apparatus described herein includeorganic molecules and natural polymers, such as organophosphates,lignins, peptides, proteins, and the like, as well as microorganismssuch as bacteria, yeast, fermenting organisms used in a fermentationprocess, and the like.

In embodiments of the processes and apparatus described herein thatinclude a fermentation step, it is appreciated that the fermentingorganism used in a fermentation process may have specific requirementsfor using various nutrients including carbohydrate, protein, nitrogen,sodium, potassium, calcium, phosphate, and others. Because the inputstream of waste fed to the fermenting organism may not have theidentical ratio of such components that matches the requirements of theorganism, after the fermentation, one or more nutrients may remain asthe supply of limiting nutrients are exhausted. It is understood thatnutrients also remain when the fermentation is performed at sub-optimallevels, and even the supply of limiting nutrient is not exhausted.Illustratively, in a fermentation processes, the limiting nutrient maybe carbohydrate, and there may therefore be a relative abundance ofother nutrients, such as phosphorus and nitrogen-containing compounds orcomponents, in the aqueous solution exiting the fermentation step afterthe supply of carbohydrate is exhausted by the fermenting organism. Whenthe absolute level of phosphorus, nitrogen, or some other component ishigher than that which may be discarded as clarified, cleaned, orpurified water, the processes and apparatus described herein may be usedto remove a portion of this phosphorus, nitrogen, or other componentsufficient to allow disposal of the aqueous solution as clarified,cleaned, or purified water.

In one embodiment, the aqueous solution includes phosphorus that may beremoved. The phosphorus may be present in the aqueous solution asinorganic phosphates, or salts thereof, and/or as organic phosphates,including intermediates and metabolites of biochemical and biologicalprocesses, such as glucose phosphates, nucleotides, cyclic-AMP, ADP, andderivatives thereof, phytic acid and other phosphoinositols, and thelike, and partial degradation products thereof. The phosphorus may alsobe present in aqueous solutions as components of microorganisms,bacteria, yeast, fermenting organisms, and the like. It is appreciatedthat in aqueous solutions containing phosphorus-containing componentsthat exit a fermentation process, the major phosphorus-containingcomponents may be organic phosphates. It is understood that somefermenting organisms will preferentially use inorganic phosphatespresent in the biomaterial waste stream before using organic phosphates.However, it is also understood that other fermenting organisms may useorganic phosphates preferentially, or use inorganic or organicphosphates equally. Still other fermenting organisms may use phosphataseenzymes, such as phytase, nucleosidase enzymes, and the like tofacilitate the use of organic phosphates.

It is understood that in embodiments that include a fermentation step,the aqueous solution provided to the processes and apparatus forremoving solids described herein may also contain sodium, potassium,ferrous, ferric, chloride, hydroxide, carbonate, sulfate, and otherions, and salts. It is further understood, that if sufficient sodiumand/or potassium are present, phosphate remains soluble. The addition ofcatalysts such as divalent metal ions, trivalent metal ions, transitionmetal ions, and/or polymeric components may allow complexes to form withthe phosphate, and possibly other anions, including carbonate andsulfate. At predetermined pH levels, these complexes may not be soluble,or may not remain suspended in the aqueous solution.

Aggregation catalysts that may be used in the processes and apparatusdescribed herein include divalent metal ions, trivalent metal ions,transition metal ions, and polymeric components. In one aspect, thedivalent and trivalent metal ions include calcium and aluminum, and thelike. In another aspect, the transition metal ions include iron, cobalt,nickel, copper, chromium, molybdenum, and the like. It is appreciatedthat transition metals such as iron and copper may provide moreflexibility in disposal of precipitates, aggregates, absorption and/oradsorption complexes that are formed. In another aspect, aluminum ionsmay be added as aluminum sulfate, aluminum hydroxide, aluminumsilicates, other silicates, silicas, BENTONITES, clays, vermiculites,and the like. It is appreciated that in embodiments of the processes andapparatus described herein where a fermentation of barn waste process isincluded, the aqueous solution may already include ample aluminum saltsarising from the ingestion of soils, such as aluminum rich clay soils,by the barn animals generating the waste.

In one embodiment, inorganic phosphates and organophosphates areprecipitated, aggregated, or otherwise removed from an aqueous solutionusing calcium ions, other divalent cations, or other Group IIA metalions. In variations of this embodiment, ferric ions, aluminum ions,and/or anionic or non-ionic polymers are also included. In anotherembodiment, sulfate is precipitated from an aqueous solution usingcalcium ions, other divalent cations, or other Group IIA metal ions. Invariations of this embodiment, ferric ions, aluminum ions, and/ornon-ionic polymers are also included. Illustratively, the calcium ionsderive from calcium hydroxide, calcium oxide, calcium chloride, and thelike. Illustratively, the ferric ions derive from ferric hydroxide,ferric chloride, ferric sulfate, and the like. Illustratively, thealuminum ions derive from aluminum sulfate, aluminum hydroxide, aluminumchloride, and the like. Illustratively, the non-ionic polymer is apolyvinylpyrrolidone (PVP), including a PVP having an average molecularweight of about 300,000 or greater, or about 600,000 or greater. Thenon-ionic polymer may also be a partially hydrolyzed polyacrylamide,including a partially hydrolyzed polyacrylamide that has been hydrolyzedby about 30%. The non-ionic polymer may also be one or more polymerizedBENTONITES, including polymerized BENTONITES that include a partiallyhydrolyzed polyacrylamide, vermiculite, silica, and the like. In thecase of polymers that include BENTONITES, commercial sources may be insodium and/or potassium forms. It is appreciated that such BENTONITESmay be converted to other forms, including ferric forms, by washing thecommercial material with a solution of the desired counterion, such as asolution of ferric sulfate, ferric chloride, and the like.

In another embodiment, the aqueous solution includes dissolved andundissolved solids, such as natural polymers, lignins, hemicelluloses,proteins, bacterial components, microorganisms, and the like. Thesesolids may be removed using the processes and apparatus describedherein. In one aspect, these solids are removed by treating the aqueoussolution with ferric ions and non-ionic polymers as described herein. Itis understood that the ferric ions and the non-ionic polymers may formaggregation, absorption, adsorption, or other complexes with thesecomponents and either remove them from the aqueous solution, or furtheraggregate to form larger aggregates or particles that may settle out ofthe aqueous solution. It is appreciated that the solubility of thesenatural polymers, including lignins, celluloses, and proteins, isdependent on their molecular weights, the pH of the aqueous solution,the ionic strength of the aqueous solution, and other physicalparameters. In another aspect, the conditions that are substantiallyoptimal for removing phosphorus-containing components may alsoeffectively remove natural polymers, lignins, hemicelluloses, proteins,bacterial components, microorganisms, and the like.

The pH of the aqueous solution may be raised above acidic levels, toneutrality, to pH levels near or at the corresponding isoelectric pointof the aqueous solution, or to a more alkaline pH by adding a base suchas lime, slake lime, powdered limestone, calcium oxide, calciumchloride, sodium hydroxide, potassium hydroxide, carbonates andbicarbonates, including sodium, potassium, and calcium carbonates andbicarbonates, sulfates, including sodium, potassium, and calciumsulfates, and the like, and combinations thereof. In some variations,the various sources of lime, slake lime, and limestone may also includea percentage of iron salts. In other variations, a ferric form of clayis added to the aqueous solution. The choice of a pH level depends onthe solubility characteristics of the dissolved or undissolved solidsthat are to be removed from the aqueous solution. For example, anaqueous solution that includes inorganic and/or organic phosphatecomponents is treated with an iron salt, such as ferric sulfate, anon-ionic polymer, such as PVP, and a base, such as calcium oxide. Thebase is added to achieve a pH near or at the pH corresponding to theisoelectric point of the aqueous solution. Without being bound bytheory, it is believed that the association of iron, PVP, and inorganicand/or organic phosphates is strongest at the isoelectric point. It isunderstood that such strong association contributes to large and/ordense particles, precipitates, aggregates, crystals, and absorption andadsorption complexes of iron, PVP, and inorganic and/or organicphosphates. Similar procedures may be used for aqueous solutions thatinclude inorganic and/or organic sulfate components.

In variations of the processes described herein, the variousprecipitation or aggregation catalysts are added as separate components.In other variations, certain mixtures of precipitation or aggregationcatalysts are added together either contemporaneously or as a preparedmixture. Illustratively, the non-ionic polymer and the transition metalions are added as a mixture. In another aspect, the non-ionic polymer,the transition metal ions, and a portion or all of the calcium, otherdivalent cations, or other Group IIA metal ions are addedcontemporaneously, where the non-ionic polymer and the transition metalions may optionally be added as a mixture.

The processes and apparatus described herein also use predetermined pHlevels to facilitate the removal of dissolved and undissolved solidsfrom aqueous solutions. Phosphate, sulfate, and other salts, andorganophosphate compounds that might be removed from aqueous solutionshave different solubilities at different pH levels. For example, bothphosphate and sulfate salts of calcium are less soluble at higher pHlevels than may be used during fermentation processes.

In addition, it is understood that gradual changes in pH may promote theformation of larger particles or crystals, where rapid changes in pH maylead to amorphous or finely divided solids. It is further understoodthat settling rates will generally follow the Reynolds equation, wherethe settling rate is inversely proportional to the square of theeffective surface area of the particle. Therefore, particles of similardensity will settle as a function of particle size, the larger of whichtend to settle first. When particles are below a certain size, arefinely divided, or amorphous, the settling rate may slow to an unusablerate. It is understood that in embodiments where particles settle bygravity, the settling rate is inversely proportional to the square ofthe effective surface area of the particle, and proportional to gravity.

Illustratively, the predetermined pH for precipitating and/oraggregating the dissolved and undissolved solids in the aqueoussolutions is in the range from about 6 to about 8, in the range fromabout 6.5 to about 7.5, and is illustratively about 6.8. In somevariations, the pH change may be performed in two steps, where the pH ischanged rapidly to a point below the predetermined level, and thenchanged slowly to the predetermined level to maximize the size ofparticles precipitating from or aggregating in the aqueous solution.Illustratively, the pH may be changed rapidly to a level in the rangefrom about 6.0 to about 6.5, or illustratively to about 6.4. After therapid pH change, the pH is increased more slowly to the predetermined pHlevel.

The dissolved and undissolved solids removed from the aqueous solutionmay be periodically removed from the processes and apparatus describedherein, such as in the form of a phosphorus rich clay. The resultingclarified water may also be periodically removed from the processes andapparatus described herein. It is understood that the phosphorus richclay may contain calcium phosphate and other inorganic forms ofphosphorus, as well as organic molecules containing phosphorus. Inparticular, it is understood that such inorganic and organic phosphatesmay form complexes with calcium, iron, and/or carbonate, that may beinsoluble at high pH and subsequently form a precipitate or otheraggregation that may be separated from the aqueous solution. Theprocesses may be performed in a batch mode, a continuous mode, or in aseries of batch cycles that may be run continuously.

In other embodiments, an excess of nitrogen-containing components ispresent in the aqueous solution. In one aspect where the aggregationprocesses described herein are used in conjunction with fermentationprocesses, such as those described herein, the fermentation process maycause most of the nitrogen-containing compounds to be an inorganic formof nitrogen due to enzymatic activity encountered during fermentation byfermenting organisms. In one embodiment, fermentation gases such ascarbon dioxide that are recycled from the fermentation processes, maysubsequently be contacted with the aqueous solution to facilitate theremoval of nitrogen. The resulting ammonium carbonates may be removedfrom the aqueous solution by degassing, and collecting the nitrogen asammonia. In addition, excess carbonate in the aqueous solution may alsofacilitate aggregation of other inorganic cations; it is understood thatmany carbonate salts are less soluble at alkaline pH than theircorresponding sulfate salts, including carbonate salts of divalentmetals.

An illustrative embodiment of the apparatus described herein forremoving dissolved or undissolved solids by precipitation, aggregation,crystallization, absorption, and/or adsorption is shown in FIG. 49.Anions such as phosphates, sulfates, carbonates, and the like, cationssuch as calcium, potassium, iron, aluminum, and the like, organicmolecules such as organophosphates, peptides, proteins, lignins, and thelike, and organisms such as fermenting organisms, bacteria, yeast, andthe like, may be illustratively removed using the system shown in FIG.49. Referring to FIG. 49, aqueous solution AS enters aggregation unit2110. It is understood that aqueous solution AS may be an aqueoussolution exiting a fermentation process or apparatus, such as afermentation process or apparatus described herein.

Aggregation unit 2110 includes one or more aggregation tanks 2130 eachincluding a liquid inlet LI. Liquid inlet LI is in fluid communicationwith inlet conduit 2112. Inlet conduit 2112 is in fluid communicationwith aqueous solution outlet ASO for introducing aqueous solution AS,base outlet BO for introducing base, and one or more aggregationcatalyst outlets ACO for introducing aggregation catalysts AC.Aggregation tanks 2130 also include a cleaned water outlet CWO in fluidcommunication with outlet conduit 2114, and an aggregate or precipitateoutlet PPTO, optionally coupled with a solid conveyor unit 2116.

Aqueous solution outlet ASO is in fluid communication with an aqueoussolution source 2118, such as the outlet of a fermentation system, areservoir or lagoon containing an aqueous solution to be treated, andthe like, and is in fluid communication with a pump P for pumpingaqueous solution AS from source 2118 to outlet ASO. A valve V,optionally operated by a programmable logic circuit PLC is placedbetween outlet ASO and inlet conduit 2112. Base outlet BO is in fluidcommunication with a base source 2120 containing a base as describedherein, and is in fluid communication with a pump P for pumping base Bfrom source 2120 to outlet BO. A valve V, optionally operated by aprogrammable logic circuit PLC is placed between outlet BO and inletconduit 2112. Each aggregation catalyst outlet ACO is in fluidcommunication with a corresponding aggregation catalyst source 2122, andis in fluid communication with a pump P for pumping aggregation catalystAC from aggregation catalyst source 2122 to outlet ACO. A valve V,optionally operated by a programmable logic circuit PLC is placedbetween each outlet ACO and inlet conduit 2112. In an illustrativeembodiment having three aggregation catalyst outlets ACO, firstaggregation catalyst AC₁ is supplied by a first aggregation catalystsource 2122 ₁ in fluid communication with outlet ACO₁, secondaggregation catalyst AC₂ is supplied by a second aggregation catalystsource 2122 ₂ in fluid communication with outlet ACO₂, and thirdaggregation catalyst AC₃ is supplied by a third aggregation catalystsource 2122 ₃ in fluid communication with outlet ACO₃. It is understoodthat in variations of the apparatus, any of the first, second, third, orsuccessive aggregation catalysts AC may be premixed with another one ormore of the other aggregation catalysts AC, and the mixture is pumpedinto inlet conduit 2112 through one of aggregation catalyst outlets ACO.

As described herein, addition of base to aggregation tanks 2130 may takeplace in two steps or as a two-stage process. In the first step orstage, the majority of the base is added to adjust the pH of the aqueoussolution to a pH level near the optimal pH level for aggregation orprecipitation. In the second step or stage, a slower addition of base ismade to adjust the pH of the aqueous solution to a pH level at thepredetermined optimal pH level for aggregation or precipitation. Therapid addition of base may take place during of after fillingaggregation tanks 2130. The slow addition of base may take place afterfilling aggregation tanks 2130. In one aspect, rapid addition of base isperformed during the filling of a first aggregation tank 2130. Afterfilling first aggregation tank 2130, a second aggregation tank 2130begins to fill, and a slow addition of base starts in the firstaggregation tank 2130. Valves V controlling base addition from baseoutlet BO to aggregation tanks 2130 may be operated in a time-sharesense in that while second aggregation tank 2130 is filling and base isbeing added rapidly, base is intermittently added to first aggregationtank 2130 to effect the second stage of the base addition. Inalternative embodiments, a separate base source BS (not shown) suppliesbase to aggregation tanks 2130 for the slow or fine pH adjustment stepor stage.

In one aspect, aggregation unit 2110 includes one or more aggregationtanks 2130. In another aspect, aggregation unit 2110 includes two ormore aggregation tanks 2130. In another aspect, aggregation unit 2110includes three or more aggregation tanks 2130. In another aspect,aggregation unit 2110 includes four or more aggregation tanks 2130. Itis appreciated that the number of aggregation tanks 2130 may depend uponthe settling rate of aggregate or precipitate PPT, so that moreaggregation tanks 2130 are used with slower settling aggregates orprecipitates PPT, and fewer aggregation tanks 2130 are used with fastersettling aggregates or precipitates PPT for a given volume processingrate. It is appreciated that in some embodiments, aqueous solution AS isa dilute solution of dissolved and/or undissolved solids; therefore,aggregates or precipitates PPT are removed from aggregation tanks 2130through outlet PPTO only occasionally.

In an embodiment where aggregation unit 2110 includes one aggregationtank 2130, the system is run in a batch mode. In the embodiments whereaggregation unit 2110 includes more than one aggregation tank 2130, thesystem is run in a continuous mode, where one tank 2130 is filling whilethe remaining tanks 2130 are in varying stages of settling or are beingemptied of cleaned water CLW or aggregate or precipitate PPT.

Referring to FIGS. 50A and 50B showing detail for each of the one ormore aggregation tanks 2130, in one illustrative embodiment, aggregationtanks 2130 have a generally sloped bottom 2138 to facilitate the removalof aggregate or precipitate PPT through outlet PPTO located at the lowpoint of sloped bottom 2138. Sloped bottom 2138 may have an arcuate,frustoconical, or linear profile, or a combination thereof. Aggregationtanks 2130 optionally have a roof or cover 2136. In embodimentsincluding a roof or cover 2136, the roof or cover 2136 may also includeone or more vents. Aggregation tanks 2130 are also optionally fittedwith a clean water spraying unit (not shown) for facilitating thecleaning and/or maintenance of tanks 2130. Aggregation tanks 2130 arealso optionally fitted with an agitation unit 2132, a level or volumesensor, such as a pressure transducer PT, a pH sensor, such as aconductivity sensing unit CS, and/or a temperature sensor TS. Each ofthe level or volume sensors, pH sensors, and/or temperature sensors TSare also optionally coupled to one or more programmable logic circuitsPLC configured to operate one or more algorithms controlling thefilling, emptying, mixing, dwell, and other phases of the processes usedin the apparatus described herein, where the algorithms use the signalvalues obtained from these sensors. Agitation unit 2132 may be in theform of a recirculating system or pump that is fluid communication withan agitation unit outlet AUO on tank 2130, where the outlet is placed ata level L3. Liquid flow through outlet AUO is controlled by a valve Voptionally coupled to a programmable logic circuit PLC. In oneillustrative aspect, circuit PLC may operate valve V and agitation unit2132 based on a signal obtained from pressure transducer PT indicating afill level at or above level L3. Agitation unit 2132 is also in fluidcommunication with inlet conduit 2112, so that when the fill level is ator above L3, the liquid contents of tank 2130 are pumped through outletAUO, and back into inlet conduit 2112. Therefore, the contents alreadypresent in aggregation tanks 2130 are admixed with the materialintroduced into aggregation tanks 2130 through inlet conduit 2112,including aqueous solution AS, base B, and one or more aggregationcatalysts AC.

A valve V separates each liquid inlet LI into aggregation tanks 2130from inlet conduit 2112, and is optionally controlled by a programmablelogic circuit PLC. A valve V also separates each cleaned water outletCWO from aggregation tanks 2130 from outlet conduit 2114, and isoptionally controlled by a programmable logic circuit PLC. A pump P isalso in fluid communication with cleaned water outlet CWO and outletconduit 2114, and is operated to remove cleaned water from aggregationtanks 2130 as described below.

Aggregate or precipitate outlet PPTO is optionally fitted with an augerunit 2140 for removing aggregate or precipitate PPT. In embodiments thatinclude auger 2140, auger 2140 is illustratively transverse to outletPPTO, and may be in the form of a progressive cavity pump operated toperiodically remove aggregate or precipitate PPT from aggregation tanks2130. Auger 2140 also includes a motor M. In one illustrative aspect,motor M may include a torque sensing unit (not shown) that is capable ofacting as a shutoff controller for auger 2140. For example, as themeasured torque falls below a predetermined threshold level because ofthe removal of a desired or predetermined amount of aggregate orprecipitate PPT, the torque sensing unit will shut down auger 2140.Aggregate or precipitate PPT that is removed by auger unit 2140 is movedto conveyor unit 2116.

The one or more aggregation tanks 2130 are also each fitted with acenter post 2146 aligned with an axis of tank 2130 and supported at thetop of tank 2130 by supports 2142, and at the bottom of tank 2130 bysupports 2144. A hollow floating assembly 2150 is coupled with centerpost 2146 in a manner that allows floating assembly 2150 to slide up anddown center post 2146 according to the level of the liquid in tanks2130. Floating assembly 2150 may slide along center post 2146 between abottom position L1, and a top position L2. Bottom position L1 is at ornear the emptied level of aggregation tanks 2130, and top position L2 isa position at or near the filled level of aggregation tank 2130. It isunderstood that levels L1 and L2 do not necessarily define the completecapacity of aggregation tank 2130. Each floating assembly 2150 has oneor more inlets FAI, which are in fluid communication with the hollow offloating assembly 2150, and the contents of aggregation tanks 2130.Floating assembly 2150 is coupled to a floating conduit 2160 in fluidcommunication with cleaned water outlet CWO. Cleaned water outlets CWOmay be placed at about the vertical midpoint between levels L1 and L2 ofaggregation tanks 2130. Cleaned water outlet CWO is also in fluidcommunication, controlled by valve V, with a pump P capable of pumpingcleaned water through inlets FAI into hollow floating assembly 2150,subsequently into floating conduit 2160, and subsequently to cleanedwater outlet CWO. As cleaned water exits aggregation tank 2130, and thelevel of liquid in aggregation tanks 2130 moves lower, and floatingassembly 2150 moves downward along center post 2146 with the level ofliquid continuing to release cleaned water into cleaned water outlet CWOuntil it reaches a predetermined location or level L1 above the bottomof aggregation tank 2130. Agitation unit 2132 is placed at apredetermined level L3 in aggregation tanks 2130 to minimize agitationof aggregate or precipitate PPT that has already settled in aggregationtanks 2130 and entered outlet PPTO. In addition, liquid inlet LIsupplying aqueous solution AS, base B, precipitation catalysts AC, andrecirculated contents from aggregation tank 2130 is place at a level L4.Level L4 is also selected so as to minimize agitation of aggregate orprecipitate PPT that has already settled in aggregation tanks 2130 andentered outlet PPTO.

In one embodiment, floating assembly 2150 is in the form of a floatingring sparger that includes a hollow tube 2154 to provide buoyancy tofloating assembly 2150, a ring sparger 2156 that includes one or moreinlets FAI in fluid communication with the hollow space of sparger 2156,and a support structure for floating assembly 2150 that includes aseries of upper horizontal supports 2152A and lower angled supports2152B that are coupled with center post 2146. In one aspect, floatingconduit 2160 is configured to spool onto floating assembly 2150, suchthat as floating assembly 2150 lowers to or rises to the level ofcleaned water outlet CWO, floating conduit 2160 will spool onto floatingassembly 2150. Conversely, as floating assembly 2150 rise above orlowers below the level of cleaned water outlet CWO, floating conduit2160 will unspool from floating assembly 2150. It is understood thatfloating assembly 2150 is coupled to center post 2146 in a manner thatallows floating assembly 2150 to rotate about the axis represented bycenter post 2146 and spool or unspool floating conduit 2160.

Referring to FIG. 50A, in one illustrative embodiment, aggregation tanks2130 have a low aspect ratio, as defined by the ratio of a verticaldimension to a horizontal dimension. Low aspect ratios may decrease theoverall elapsed time required for settling the particles aggregate,crystals, precipitate, absorption complex, or adsorption complex.Illustrative low aspect ratios include aspect ratios of about 2 or less,or aspect ratios of about 1 or less.

Referring to FIG. 50B, in one illustrative embodiment, aggregation tanks2130 have a circular or elliptical cross-section. In this view, optionalroof or cover 2136 is not shown for clarity. Such tanks may be generallyspherical or generally cylindrical in overall shape. In anotherillustrative embodiment, liquid inlets L1 are configured so that liquidentering aggregation tanks 2130 is directed along a side 2134 ofaggregation tanks 2130, as indicated by arrow A in FIG. 50B. Invariations where aggregation tanks 2130 have a circular or ellipticalcross-section, liquid inlets LI enter aggregation tanks 2130 at atangential point. In addition, liquid entering aggregation tanks 2130may create a vortex in aggregation tanks 2130. It is appreciated thatsuch a vortex may serve to mix the components of liquid enteringaggregation tanks 2130 with each other as well as mix the liquidentering aggregation tanks 2130 with residual material already containedin aggregation tanks 2130. It is also appreciated that such a vortex mayfacilitate the movement of precipitate or aggregate away from the sides2134 and down the sloped bottom 2138 of aggregation tanks 2130 towardoutlet PPTO.

In variations of the apparatus, aggregation tanks 2130 may be fittedwith additional liquid inlets LI that are in fluid communication withone or more aggregation catalyst outlets ACO, base outlet BO, oradditional base outlets BO. It is understood that additional baseoutlets BO may be supplied by the same or by different base sources2120. In variations where the same base source 2120 is used, analgorithm may be used to control the distribution of base as needed toany of base outlets BO ultimately in fluid communication with liquidinlets LI into aggregation tanks 2130. The algorithm may includeparameters such as elapsed time, pH, conductivity, and like inputs ormeasurements taken from aggregation tanks 2130.

In variations of the apparatus where base outlet BO is in fluidcommunication with inlet conduit 2112, inlet conduit 2112 may be fittedwith a pH sensing unit (not shown). The pH sensing unit may be in theform of two or more conductivity sensors CS, where at least one sensorCS is located upstream of base outlet BO, and at least one sensor CS islocated downstream of base outlet BO. Conductivity sensors CS arecapable of measuring a signal which may be sent to a programmable logiccircuit capable of converting the conductivity of aqueous solution AS toa pH value that may be in turn used to control the addition of basethrough alternate base outlet BO coupled to inlet conduit 2112. Invariations of the apparatus where alternate base outlet BO is coupled toinlet conduit 2112, inlet conduit 2112 optionally includes a heatexchanger (not shown) for cooling the aqueous solution as needed afterthe addition of base through alternate base outlet BO.

In one illustrative process using the apparatus shown in FIGS. 49, 50A,and 50B, aqueous solution AS enters inlet conduit 2112. In oneillustrative aspect, a predetermined amount of one or more aggregationcatalysts also enter inlet conduit 2112. The mixture then entersaggregation tank 2130 through liquid inlet LI. The conductivity of thecontents of aggregation tank 2130 is measured with a conductivity sensorCS. The signal from sensor CS is sent to a programmable logic circuitthat controls the addition of an appropriate amount of base enteringinlet conduit 2112 through base outlet BO and mixing with aqueoussolution AS. The conductivity of the contents of tank 2130 iscontinually or periodically measured to continually or periodicallyadjust the amount of base added to inlet conduit 2112. When apredetermined fill level is reaches, determined on the basis of elapsedtime or using pressure transducer PT, agitation unit 2132 is operated tohomogenize the contents of aggregation tank 2130 with the incomingstream entering liquid inlet LI so that conductivity measurements takenby conductivity sensor CS are representative of the bulk mixture ratherthan the mixture in the locale of conductivity sensor CS. An algorithmcontrols the amount of base entering conduit 2112 determined byevaluating the conductivity of the material in aggregation tank 2130,comparing that value with the difference between the desired value andthe value predicted by the last addition or adjustment to the additionof base.

For example, the pH calculated from the reading taken by conductivitysensor CS of aqueous solution AS in aggregation tank 2130 is convertedinto a predetermined amount of base entering inlet conduit 2112 throughbase outlet BO. Subsequently, the pH calculated from the reading takenby conductivity sensor CS of the contents of aggregation tank 2130 iscompared against a predicted value based on the predetermined amount ofbase entering inlet conduit 2112. If the predicted value matches thevalue measured by conductivity sensor CS of the contents of aggregationtank 2130, no change is made to the amount of base entering inletconduit 2112. If the predicted value is higher than or lower than thevalue measured by conductivity sensor CS of the contents of aggregationtank 2130, a corresponding change to the amount of base entering inletconduit 2112 is made. In one illustrative aspect, the predicted pH valueof the contents of aggregation tank 2130 is a pH level slightly belowthe predetermined pH optimal for precipitate formation during a fillingphase or step of a process described herein.

Aqueous solution AS, base B, and aggregation catalysts AC enter a firstaggregation tank 2130 through inlet ASI at a level L4, or optionally ata point about level with the lowest possible location L1 of floatingassembly 2150 to minimize agitation of the solution and aggregate orprecipitate PPT remaining in the first aggregation tank 2130 from thelast run. Aqueous solution AS, base B, and aggregation catalysts AC areadded to first aggregation tank 2130 to a fill level that may be nearthe highest possible location L2 of floating assembly 2150. Filling oftank 2130 may be controlled by using a predetermined time based on thepumping rate and tank volume, or by using a level, volume, or pressuresensor PT that indicates the fill level of first tank 2130. When thefill level L3 is reached, agitation unit 2132 is optionally operated tohomogenize the composition present in first aggregation tank 2130. Aftertank 2130 is full, valve V controlling the addition of aqueous solutionAS, base B, and aggregation catalysts AC via inlet conduit 2112 to firstaggregation tank 2130 is closed, and the corresponding valve V to secondaggregation tank 2130 is opened. The filling process as described forfirst aggregation tank 2130 begins in second aggregation tank 2130.

After first aggregation tank 2130 is full, additional base is addedthrough inlet conduit 2112, and the conductivity of the contents offirst aggregation tank 2130 is measured with conductivity sensor CS. Thecorresponding pH of the contents of first aggregation tank 2130 isdetermined from the conductivity measurement and compared to apredetermined optimum pH value for crystallization, precipitation,aggregation, absorption, and/or adsorption. Base addition into firstaggregation tank 2130 through inlet conduit 2112 is continued until themeasured conductivity corresponds to a pH value at or near thepredetermined optimum pH value as described herein. Agitation unit 2132is optionally operated during this second stage addition of base intofirst aggregation tank 2130. In an alternate embodiment, aqueoussolution AS and base B are added first, and then after the additionbase, one or more aggregation catalysts are added to first aggregationtank 2130 through liquid inlet LI. In variations of this process, amixture of a first aggregation catalyst and a second aggregationcatalyst is added to first aggregation tank 2130 through liquid inlet LIto the contents of first aggregation tank 2130.

After the addition of the one or more aggregation catalysts, additionalbase is added through liquid inlet LI, and the conductivity of thecontents of first aggregation tank 2130 is measured with conductivitysensor CS. The corresponding pH of the contents of first aggregationtank 2130 is determined from the conductivity measurement and comparedto a predetermined optimum crystallization, precipitation, aggregation,absorption, and/or adsorption pH value. Base addition into firstaggregation tank 2130 through liquid inlet LI is continued until themeasured conductivity corresponds to a pH value at or near thepredetermined optimum pH value as described herein. It is understoodthat agitation unit 2132 is optionally operated during this second stageaddition of base into first aggregation tank 2130. In an alternateembodiment, the pH is adjusted to the optimum level before the additionof the one or more aggregation catalysts.

In one aspect, after first aggregation tank 2130 is full, the additionof base to raise the pH to the predetermined optimal pH level asdescribed herein for crystallization, precipitation, aggregation,absorption, and/or adsorption is illustratively a slow rate of additionto facilitate the formation of larger particles, crystals, precipitates,aggregates, or absorption or adsorption complexes. When the optimalpredetermined pH is reached, agitation unit 2132 is stopped, andaggregation and settling begins. After a predetermined settling waitperiod, pump P is operated to remove cleaned water from tank 2130through outlet CWO via floating assembly 2150. The pumping rate ispredetermined to be about less than or about equal to the settling rateof aggregate or precipitate PPT. Pumping is continued for apredetermined time based on the pumping rate and tank volume, or until alevel or volume sensor PT indicates floating assembly 2150 has reachedis lowest allowed position. Valve V located at outlet CWO is then closedto first aggregation tank 2130, and the corresponding valve is opened tosecond tank 2130, allowing the process to run in a continuous serialbatch mode.

It is understood that several coordinated configurations are possiblewhen more than one aggregation tank 2130 is used in aggregation unit2110. In one embodiment, the elapsed time for settling and emptying offirst tank 2130 may be selected to correspond with the filling andsettling time in second tank 2130, such that upon completion of theemptying of first tank 2130, the emptying of second tank 2130 may begin.Correspondingly, the refilling of first filling tank 2130 or filling ofthird aggregation tank 2130 may begin. Other configurations are alsopossible where the filling, waiting, emptying, and idle times arecoordinated to achieve a continuous processing of aqueous solution AS.

It is further understood that during times when a particular aggregationtank 2130 is idle after an emptying step, and awaiting the next fillingcycle, the saturated precipitate solution remaining in tank 2130 may becontinually recrystallizing or reaggregating, such that larger andlarger crystals or particles are formed. Such a process may tend tominimize the amount of retained water in the aggregate or precipitatePPT slag that is periodically removed through outlet PPTO using auger2140. It is further understood that such recrystallizing orreaggregating processes may tend to promote the formation of a morecompact aggregate or precipitate PPT slag that is periodically removed.It is further understood that such a process may also tend to minimizethe amount of agitation and or re-solution of aggregate or precipitatePPT that might occur during the next filling cycle.

In one aspect of the illustrative system shown in FIG. 49, the aqueoussolution AS is a solution exiting a fermentation system, such as afermentation system described herein. In another aspect, the firstaggregation catalyst is a transition metal salt, such as a transitionmetal halide, hydroxide, or sulfate, including ferric chloride, ferrichydroxide, and ferric sulfate. In another aspect, the second aggregationcatalyst is a Group IIA metal salt, such as a calcium salt includingcalcium chloride, calcium sulfate, calcium hydroxide, and the like, or aGroup IIA metal oxide, such as calcium oxide.

In variations, additional aggregation catalysts are added, such as GroupIIIA metal salts including aluminum sulfate, aluminum hydroxide, and thelike. In other variations, one or more of the aggregation catalystsources includes a pH adjustment unit (not shown) that includes an acidsource, containing an inorganic or mineral acid such as hydrochloricacid, and a base source, containing an inorganic base such as a carbonicacid salt, including a sodium, potassium, or calcium salt thereof, anoxide, such as sodium, potassium, or calcium oxide, and the like.

In an illustrative embodiment having four aggregation tanks 2130, analgorithm using any number of a variety of signal inputs may be used tocoordinate the filling of each aggregation tank 2130, the addition ofbase, the addition of any one of the one or more aggregation catalysts,the agitation, the dwell interval for settling, the emptying ofaggregation tank 2130, and any idle interval. Signal inputs include, butare not limited to time, pH, conductivity, pressure, weight, temperaturesignal inputs, and the like. In one aspect, each of the four aggregationtanks 2130 has a known volume, and the filling phase, dwell phase,settling phase, emptying phase, and idle phase are each controlled bypredetermining a filling rate, and determining an emptying ratecorresponding to the settling rate of aggregate or precipitate PPT.

In one aspect, valve V to liquid inlet LI of first aggregation tank 2130is opened and the tank is filled with aqueous solution AS. The firstaggregation tank 2130 illustratively has a volume of 12,000 gallons(45,425 liters) and AS is pumped in at a rate of 100 gallons/min (379liters/min). Valves V to liquid inlets LI of second, third, and fourthaggregation tanks 2130 are closed. Valve V controlling base outlet BO toinlet conduit 2112 of first aggregation tank 2130 is opened and asolution of calcium oxide (calcium hydroxide) is contemporaneouslyadded. The amount of base added is controlled by measuring theconductivity of the contents of first aggregation tank 2130. The targetconductivity of the contents of first aggregation tank 2130 is thatconductivity corresponding to a pH in the range from about 6 to about 7.Agitation unit 2132 is operated throughout the filling of firstaggregation tank 2130. The tank is filled in approximately 120 minutes.Valve V controlling outlet ASO through inlet conduit 2112 and liquidinlet LI to first aggregation tank 2130 is closed after a predeterminedelapsed time or after a reading from pressure transducer indicates thatfirst aggregation tank 2130 is filled to capacity. Simultaneously, valveV controlling outlet ASO through inlet conduit 2112 to inlet LI ofsecond aggregation tank 2130 is opened and the tank is filled withaqueous solution AS. Second aggregation tank 2130 also illustrativelyhas a volume of 12,000 gallons (45,425 liters), and AS is pumped in at arate of 100 gallons/min (379 liters/min). In addition, valve Vcontrolling base outlet BO to second aggregation tank 2130 is opened anda solution of calcium oxide (calcium hydroxide) is contemporaneouslyadded. Base addition is controlled as described above for firstaggregation tank 2130. Subsequent steps in the process using secondaggregation tank 2130 proceed as described below. In addition, third andfourth aggregation tanks 2130 are used sequentially. It is understoodthat first aggregation tank 2130 reenters the process after fourthaggregation tank 2130 in a continuous cycle until the processing ofaqueous solution AS is complete.

Base addition is continued into inlet conduit 2112 into firstaggregation tank 2130, but at a slower or substantially slower additionrate, and agitation unit 2132 is continually operated. Base addition maycontinue into first aggregation tank 2130 by a time-share sequence wherebase is directed into both first and second aggregation tanks 2130 byappropriate operation of valves V controlling outlet BO into thosetanks. Alternatively, an additional base source may be used to continueto add base to first aggregation tank 2130 after it is filled and whilesecond aggregation tank 2130 is being filled. In one aspect, baseaddition is continued until a predetermined conductivity is detected byconductivity sensor CS. In another aspect, base addition is continueduntil a predetermined change in conductivity over time is detected.Valve V controlling aggregation catalyst outlet ACO to first aggregationtank 2130 is opened, and a mixture of a first aggregation catalyst,illustratively ferric sulfate, and a second aggregation catalyst,illustratively PVP, is added. Valves V to outlets ACO of second, third,and fourth aggregation tanks 2130 are closed. Illustratively, themixture of the first and the second aggregation catalysts is continuedfor a predetermined length of time based on the addition rate of themixture and the volume of first aggregation tank 2130. Valve V toaggregation catalyst inlet ACI of first aggregation tank 2130 is closed,agitation unit 2132 is stopped, and the contents of first aggregationtank 2130 are allowed to settle. After a predetermined period of time,valve V to outlet CWO of first aggregation tank 2130 is opened, pump Pis operated, and cleaned water is removed from first aggregation tank2130 through floating assembly inlets FAI into hollow floating assembly2150. In variations, instead of an elapsed time parameter, an opticalelement may be included in aggregation tanks 2130 capable of measuringthe optical density of the contents of the tank. The optical element maybe used to determine that the settling of aggregate or precipitate PPThas progressed to or past a certain point in the tank and to initiatethe removal of cleaned water from the tank. Cleaned water is pumped fromthe tank at a rate at or less than the continued settling rate ofaggregate or precipitate PPT. After cleaned water has been removed fromfirst aggregation tank 2130 to a predetermined lower level, pump P isstopped and valve V to outlet CWO of first aggregation tank 2130 isclosed. The processes in second, third, and fourth aggregation tanks2130 has continued simultaneously and is at various stages. In anotherembodiment of the processes described herein for precipitating dissolvedsolids from aqueous solutions, a process for precipitating solids fromaqueous solutions using gaseous carbon dioxide is described. It isunderstood that this process may be accomplished with the apparatusdescribed herein using modifications that allow for the introduction ofa gas containing or consisting of carbon dioxide. Such introduction maybe accomplished for example using any conventional sparger, or any ofthe sparger embodiments described herein, or incorporated herein byreference.

In one aspect of the process, an aqueous solution having any pH in therange from less than about 1 to less than about 10 or 11 is treated witha strong base or a strong base solution to raise the pH to about 10 orgreater, or to about 11 or greater. In another aspect, the pH is raisedto substantially above 11, including about 12 or about 13. In anotheraspect, the pH of the aqueous solution is raised as fast as ispracticable. After a short dwell time, illustratively about 15 minutes,or about 30 minutes, the pH is illustratively at least greater thanabout 10, or greater than about 11. It is appreciated that a dwell timemay be necessary for a pH equilibrium to be reached in embodiments wherethe pH is increased rapidly by the addition of base. slowly reduced bythe addition of a source of gaseous carbon dioxide. In another aspect,the pH is subsequently reduced to a near neutral pH in the range fromabout 6.5 to less than about 8, and illustratively in the range fromabout 6.8 to about 7.5. In another aspect, the pH is subsequentlyreduced to a slightly basic final pH in the range from greater thanabout 7 to less than about 8, and illustratively in the range fromgreater than about 7 to less than about 7.5.

It is appreciated that depending upon the gaseous source of carbondioxide, either a slightly basic pH or a nearly neutral pH may be thefinal pH. For example, if the source of carbon dioxide is that naturallyoccurring in atmospheric air, the final pH may only be slightly basic,such as less than about 8, or in the range from greater than about 7 toless than about 7.5. In contrast, if a more concentrated source ofcarbon dioxide, such as pure carbon dioxide is used to lower the pH, thefinal pH may be as low as about 6.5, or in the range from about 6.8 toabout 7.5. It is understood that sources of carbon dioxide that areintermediate in concentration, such as gases collected from thefermentation processes described herein, may provide a either nearneutral or slightly basic final pH.

It is further appreciated that in embodiments of the systems describedherein than include fermentation processes, certain fermentations mayprovide more highly concentrated sources of carbon dioxide than others.For example, it is understood than fermentation processes that useethanol generation waste or other alcohol production waste may providerelatively highly concentrated sources of carbon dioxide resulting fromthe fermentation thereof. In contrast, animal waste streams, or cheeseand whey processing waste may provide relatively lower concentrations ofcarbon dioxide sources resulting from the fermentation thereof.

It has been observed that slow decreases in pH generally providessuperior crystal quality, more highly organized, and/or more denseprecipitates, agglomerates, and/or aggregates, that may alsoconcomitantly trap less water or other solvent. These attributes of theresulting precipitates, agglomerates, and/or aggregates tend to decreasesettling times and increase the overall purity of the clarified waterproduced in the processes described herein.

In another embodiment of this precipitating process, only carbon dioxideis added to the tank to cause precipitation of the remaining phosphoruscompounds as carbonate salts. It is understood that within optimallyselected pH ranges, carbonate salts of phosphate are less soluble thansulfate salts of phosphate, such as the sulfate salts produced in theacidifying steps of other processes described herein for treatingbiomaterial waste streams. It is understood that carbon dioxide isproduced during the fermentation processes, and therefore that carbondioxide may be trapped and used in the subsequent post processing stepsto remove dissolved solids, such as phosphate solids. In thisembodiment, the pH is adjusted higher by the addition of a base. It isappreciated that the addition of carbon dioxide will also alter the pHof the liquid being treated, and therefore subsequent addition of baseis performed while taking account of the pH change causable by thecarbon dioxide addition.

In another aspect, gaseous carbon dioxide is added via a sparger orother dispersing apparatus that decreases bubble size, allowing rapidmixing and minimizing the generation of local high concentrations ofcarbon dioxide in the aqueous solution being treated. It is thereforeappreciated that both the rate and concentration of gaseous carbondioxide in a gaseous input stream may be adjusted and modified toachieve a slow decrease in the pH of the aqueous solution being treated.For example, at one illustrative extreme, pure carbon dioxide gas may beadded very slowly, optionally following a syncopated or metered profile,where small amounts of carbon dioxide are added, then a dwell period isincluded, followed by subsequent additional carbon dioxide gas. Atanother illustrative extreme, atmospheric air containing as little asabout 0.03% to about 0.04% carbon dioxide may be added at a faster rate,with or without intermittent dwell periods. It is appreciated that belowa certain threshold concentration and at a maximum addition rate, theaddition time will be necessarily increased to ensure completeprecipitation, or the obtention of a predetermined pH in the aqueoussolution being treated. Other intermediate concentration sources ofgaseous carbon dioxide include exhaust gases exiting the fermentationapparatus and processes described herein. The enrichment of carbondioxide in those exhaust gases will likely depend upon the fermentingorganism used and the nature of the components of the biomaterial wastestream being fermented. For example, biomaterial waste streamscontaining large amounts of ethanol, such as alcohol fermentation andproduction waste streams may tend to produce exhaust gases richer incarbon dioxide than may be produced by the fermentation of barn of swinewaste. Regardless, at intermediate concentrations, the addition rate andaddition time may be adjusted accordingly to achieve the predeterminedrate of pH change. Further, the above sources of carbon dioxide, as wellas other conventional sources, may each be further enriched by theaddition of a purer source of carbon dioxide from an auxiliary tank orsource, or be further diluted by the addition of atmospheric air.

In one illustrative variation, the pH may be monitored to determine whenthe final predetermined pH is achieved. In another variation, the pH isnot monitored, rather estimates of sufficient time may be followed andthe predetermined pH is achieved on the basis of an equilibrium beinggenerated by the buffering supplied by the carbonic acid and saltsthereof generated from the added carbon dioxide in conjunction withother non-precipitated components in the aqueous solution being treated,including carbonate and bicarbonate salts of calcium.

In one illustrative example, atmospheric air is used as the source ofcarbon dioxide, which is bubbled into about 180,000 to about 190,000gallons (from about 680,000 to about 720,000 L) of an aqueous solutionincluding phosphorus components among others. The air is introduced at afast rate in the range from about 1500 to about 2000 ft³/min (from about42 to about 57 m³/min), and illustratively at a rate of about 1700ft³/min (about 48 m³/min), overnight for about 10-16 hr or for about 14hr.

It is understood that like other processes described herein for removingdissolved solids from aqueous solutions, this embodiment maysubstantially reduce the amount of dissolved inorganic and organicphosphorus components, inorganic and organic nitrogen components, andthe like, as well as other organic components that may contribute tochemical oxygen demand (COD) or biological oxygen demand (BOD), byprecipitating the same as carbonate complexes. Phytic acid, a majorcomponent of animal waste-based biomaterial waste streams may also bespecifically removed by this process. It is understood that phytic acidmay generally not be decomposed by most fermenting organisms without theaddition of phytases as described herein. Lignins and other coloredorganic components may also be specifically removed by this process.

Without being bound by theory, it is believed that in dilute aqueoussolutions continuing dissolved solids, the initial rapid rise in pHcauses the formation of insoluble salts of the components that areultimately removed by precipitation. However, the dilute nature of theaqueous solution being treated may preclude the formation of largecrystals for kinetic reasons, especially in large scale operations. Itis therefore believed that such insoluble salts of the components thatare ultimately removed by precipitation initially associate with calciumand subsequently with carbonate to either form complexes with each otheror simply form larger and denser carbonate crystals, replacing thesmaller hydroxide crystals. Settling times are therefore increased,along with the efficiency of dissolved solid removal. In any case, theclarified water exiting such dissolved solid precipitation processes andapparatus may be disposed as non-hazardous waste water. In particular,the processes described herein that use gaseous carbon dioxide generallyachieve the near neutral pH range required for non-hazardous wastedisposal.

EXAMPLES EXAMPLE 20 Illustrative Core Process with Optional AlternateProcesses

Steps of an illustrative process are shown FIG. 51. The process shown inFIG. 51 includes a core process and two separate and optional treatmentsteps, a pretreatment process and a post treatment process. The coreprocess includes pumping (step 1), separating large and/or heavyparticles, including sand (steps 2 & 3), separating solids, includingfiber, from liquids (steps 4 & 5), adjusting the pH (steps 7 & 8),sterilizing (step 9), fermenting (step 10), and collecting yeast (step11). In another illustrative embodiment, a pretreatment process may beincluded, and tailored to the particular biomaterial waste streamintroduced into the process shown in FIG. 51. In one illustrativeaspect, the pretreatment process includes collecting washed fibers fromsolid/liquid separation (steps 4 & 5), extracting the washed fibers,reintroducing the extract into the liquid stream (steps 5 & 6).Remaining solids from the extraction may be discarded, or alternatively,the extracted solids may be recycled into the process. In anotherillustrative embodiment, a post-treatment process may be include, andtailored to the particular biomaterial waste stream introduced into theprocess shown in FIG. 51. In one illustrative aspect, the post-treatmentprocess includes collecting the liquid from fermentation (step 10), andaggregating or precipitating any dissolved or undissolved solids,including excess nutrients such as phosphorus-containing components,sulfate-containing components, and the like (steps 12 & 13). Theresulting cleaned liquid may be discarded, or alternatively, the cleanedliquid may be used a source of clean water in any one or more of theclean water inlets CWI included in the processes and apparatus describedherein.

In particular, step 1 includes pumping a biomaterial waste stream thatmay be a combination of solids and liquids. Waste material may be pumpedfrom a suitable collection point by a sump pump designed to pump thewaste material without clogging. Very large particles may be excluded byentry screens, grates, and the like. Separation of sand, rocks, andother large debris may be accomplished in step 3, where a solidsentrainment and sand separation tank may receive the pumped material,and agitate the pumped material allowing the waste to be deposited onthe bottom of the tank. Periodically this material may be allowed todischarge from the bottom of the tank into a reservoir, where it iswashed with water (step 2), and then discharged.

The remaining liquid containing relatively lighter solids, is pumped toa liquid/solid separator (steps 4 & 5) where a vibratory filter screenmay be used to separate the majority of solids from liquid. A water wash(step 4) may be used to dilute liquid saturating the solids, to enablehigher recovery of nutrients and/or pollutants dissolved in the liquid.The solids, including fiber, cellulosistic, and other materials, may bedirectly discharged from the process at this point (step 5b), and may beoptionally treated in a pretreatment process. Illustratively, thepretreatment process shown in FIG. 51 includes an acidsolubilization/hydrolysis process as described herein. When a highcontent of cellulosistic material is present in the solid material, itis appreciated that a greater concentration of nutrients may beextracted by dilute sulfuric acid hydrolysis of the solid material. Itis understood that other pretreatment processes described herein may beused to treat the separated solids. After treatment, the separatedsolids may be extracted, and the extract reintroduced to the process(step 5c) for pH adjustment (steps 7 & 8). Alternatively, the combinedseparated liquids are pumped to a dual, backwashing final filter, andthen to pH adjustment (steps 7 & 8).

The pH adjustment may be accomplished by metering an acid as describedherein, such as sulfuric acid into the liquid stream (step 8).Alternatively, if the pH is too low, a base as described herein, such ascalcium hydroxide is added to the liquid stream to adjust the pH to ahigher level. The pH may be determined in some embodiments by measuringthe conductivity of the liquid. Following pH adjustment, the liquid maybe sterilized (step 9), and fermented (step 10). Sterilization may beaccomplished by heating the liquid, optionally under pressure, in aninsulated loop of pipe. Illustratively, the liquid stream is heated forabout 3 minutes, after which time the liquid is cooled. In alternateprocesses, the sterilized liquid may be heat exchanged with incomingliquid to both cool the sterilized liquid and recover a portion of theheat. The fermentation process (step 10) may include an air-lift designusing sterile air that allows the fermenting organism, such as a yeastspecies, to convert carbon-containing compounds found in the liquidstream to a mass or population of fermenting organism. Population growthmay also remove substantial amount of phosphorus, nitrogen, potassium,and other components from the liquid stream. Fermentation rates may becontrolled by controlling the population of the fermenting organism asdescribed herein. The progress of fermenting organism growth may bemonitored, and excess fermenting organism may be removed from the systemas it is detected (step 11b) to slow fermentation when necessary.Collected fermenting organism product may be subjected topasteurization, cooled, and/or stored. Liquid exiting the fermentationprocess (step 11a) may be discarded or the process may include apost-treatment process for removing excess dissolved and undissolvedsolids remaining in the liquid stream following fermentation (steps 12 &13). The liquid stream may be treated with a precipitating or otheraggregating catalyst as described herein, such as calcium ions to removedissolved and undissolved solids remaining in the liquid stream. It isunderstood that other precipitating or aggregating catalysts, includingiron salts, and non-ionic polymeric components may be included in theexcess solids aggregation process. Aggregated, precipitated, or adsorbedsolids are removed (step 13b), and the cleaned liquid (step 13a) may bediscarded, or alternatively used as a source of clean water for theprocesses and apparatus described herein.

It is understood that the process described in FIG. 51 may be used toremove components from a biomaterial waste stream where the componentsin the biomaterial waste stream are considered pollutants orcontaminants, and/or used to grow a population of a fermenting organismwhere the components in the biomaterial waste stream serve as nutrientsfor the fermenting organism.

EXAMPLE 21 Process Mass Balance for Barn Waste from a Core Process

A sample of barn waste was diluted with water to prepare a slurrycontaining about 4% solids content. Large debris was removed by settlingfor about 1 minute, and the supernatant was decanted away. It isunderstood that this settling technique performed on a smaller scaleapproximates results obtained when the solid/liquid separation isperformed on a larger scale using the shaker screen process andapparatus described herein. It has been observed that centrifugation ofthe diluted barn waste removed a greater percentage of the solids,including bacteria. A chemical oxygen demand (COD) determination wasmade on the supernatant according to standard EPA testing protocols, andthe results are presented in Table 12. Fresh scrapings of the residuewere diluted to about 4% solids content (by reference to the moistureand ash free weight determination). The percentages of sand andundissolved minerals was estimated by decanting redissolved ashresidues.

Analysis for various components was performed at selected steps shown inFIG. 51, and the results are presented in Table 12. The data in Table 12are representative of the performance of an illustrative embodiment ofthe invention, and are a compilation of data and results obtained fromseveral batch and continuous flow experiments. Batch experiments wereperformed on a scale in the range from about 30 to about 250 mL, andcontinuous flow experiments were conducted using 2 L fermentationequipment. Fermentation was otherwise performed using conventionalequipment and standard procedures. For example, batch fermentation wasperformed in flasks and the contents during fermentation were agitatedon a shaker table. The values in Table 12 have been normalized to a 100gallon (379 liter) per minute continuous flow process, as describedherein. TABLE 12 Analysis results from Example 21 at selected steps.Step^((a)) Stream Water^((b)) Sand^((c)) Fiber^((d)) P^((e)) N^((f))COD^((g)) SO₄ ^(2−(h)) Ca^(2+(i)) Yeast^((j)) 1 BW^((k)) 363.3 5.0 9.9104.4 596.4 4,994.5 2 water 14.9  3b sand 2.3 4.5 0.1 1.3 7.4   61.9 4water 39.4  5a liquid 385.2 101.2 578.4 4,844.4  5b solid 19.7 0.5 9.91.8 10.5   88.3 8 H₂SO₄ 1.2 9 liquid 385.2 101.2 578.4 4,844.4 1.2 11aliquid 369.1 31.2 428.5 11b yeast 16.1 70.0 149.9 0.1 4.0 % 70.1% 28.2% 100% reduction^((a))Referring to FIG. 51^((b))Liters/min;^((c))typical sand bedded dairies in kilograms/minute;^((d))kilograms/minute of non-dissolved solids without sand;^((e))grams/minute total organic and inorganic phosphorus;^((f))grams/minute total organic and inorganic nitrogen;^((g))Chemical Oxygen Demand, in grams/minute is a measurement thatapproximates the organic content of the stream;^((h))Kilograms/minute, allows tracking of sulfuric acid added to theprocess;^((i))Kilograms/minute, allows tracking of calcium oxide (lime) added tothe process,^((j))Kilograms/minute;^((k))raw dairy barn waste normalized to a continuous flow of 100gallons/minute (379 liters/minute) of a 4% total solids concentration(excluding sand).

The data in Table 12 indicate that the core process alone removed 100%of the COD, and a substantial portion of the phosphorus-containing andnitrogen-containing components, 70% and 28%, respectively. Yeastproduction is high at a ratio of 1.2:1 for COD/yeast (kg/kg).

EXAMPLE 22 Process Mass Balance for Barn Waste from a Core Process and aPretreatment of Washed Fiber

The procedure of Example 21 was followed to prepare the first extract.In addition, the fiber removed at step 5b was placed in a cylinder andwashed with water in a countercurrent direction. The velocity of waterflow was adjusted to exceed the settling speed of small fibers ofcellulose and/or lignin particles. The wash water was allowed to flowover the upper edge of the cylinder and was discarded. After water flowwas discontinued, the remaining water in the cylinder was drained awayleaving the washed fiber behind, primarily the large and/or relativelyheavy material. The washed fiber was treated with a minimum amount of70-80%, or 72-78% H₂SO₄ at ambient temperature for about 30 minutes to 1h. This mixture was diluted with water to 3% H₂SO₄, and the mixture washeated at 121° C. for 1 h in a pressure vessel (autoclave). Aftercooling, the mixture was filtered and a COD determination was made onthe filtrate according to standard EPA testing protocols, and theresults are presented in Table 12. The second extract was added thefirst extract and the pH adjusted within the range from about 4.0 toabout 4.5 by accordingly adding the appropriate amount of H₂SO₄ orcalcium carbonate. Precipitated calcium sulfate was optionally removedif present.

In variations, before the mixture was diluted with water to 3% H₂SO₄,the concentrated sulfuric acid was substantially removed. It was foundthat there was sufficient sulfuric acid remaining with the mixture toobtain a 3% H₂SO₄ solution capable of preparing the second extract. Theremoved sulfuric acid may be recycled into this or other processesdescribed herein. In other variations, the mixture was diluted first toan intermediate concentration in the range from about 20% to about 50%,and illustratively about 30%. The first dilution to 30% caused thepartially hydrolyzed or partially solubilized solids to gel. Thisintermediate dilution was optionally performed with cooling. The excessliquid was removed, and the gel was diluted with water to form the 3%H₂SO₄ solution. The removed sulfuric acid solution may be recycled intothis or other processes described herein.

Analysis for various components was performed at selected steps shown inFIG. 51, and the results are presented in Table 13. TABLE 13 Analysisresults from Example 22 at selected steps. Step^((a)) Stream Water^((b))Sand^((c)) Fiber^((d)) P^((e)) N^((f)) COD^((g)) SO₄ ^(2−(h)) Ca^(2+(i))Yeast^((j)) 1 BW^((k)) 363.3 5.0 9.9 104.4 596.4 4,994.5 2 water 14.9 3b sand 2.3 4.5 0.1 1.3 7.4   61.9 4 water 39.4  5a liquid 385.2 101.2578.4 4,844.4  5b solid 19.7 0.5 9.9 1.8 10.5   88.3  5c liquid 1,970.91.2 6 H₂SO₄ 39.4 1.2 9 liquid 365.5 101.2 578.4 6,815.2 1.2 11a liquid365.7 17.1 398.1 11b yeast 19.6 84.1 180.4 0.1 4.9 % 83.6% 33.3%  100%reduction^((a))See legend for Table 12.

The data in Table 13 indicate that pretreatment of the fiber collectedfrom solid/liquid separation step 3 and reintroduction of the extractinto the fermentation step 6 results in a higher removal of bothphosphorus-containing and nitrogen-containing components compared to theprocess of Example 21. In addition, the yeast yield was increased overthe process of Example 21.

EXAMPLE 23 Process Mass Balance for Barn Waste from a Core Process and aPost Treatment

The procedure of Example 21 was followed to prepare the first extract.

In addition, after fermentation, the resulting liquid was treated with amixture of ferric sulfate and poly(vinylpyrrolidone) and the pH of thesolution was rapidly adjusted to about 6.5 and slowly adjusted to 6.8.The pH was monitored with a pH meter. The mixture was allowed to settle,and the supernatant was analyzed.

Analysis for various components was performed at selected steps shown inFIG. 51, and the results are presented in Table 14. TABLE 14 Analysisresults from Example 23 at selected steps. Step^((a)) Stream Water^((b))Sand^((c)) Fiber^((d)) P^((e)) N^((f)) COD^((g)) SO₄ ^(2−(h)) Ca^(2+(i))Yeast^((j)) 1 BW^((k)) 363.3 5.0 9.9 104.4 596.4 4,994.5 2 water 14.9 3b sand 2.3 4.5 0.1 1.3 7.4   61.9 4 water 39.4  5a liquid 385.2 101.2578.4 4,844.4  5b solid 19.7 0.5 9.9 1.8 10.5   88.3 8 H₂SO₄ 1.2 9liquid 385.2 101.2 578.4 4,844.4 1.2 11a liquid 369.1 31.2 428.5 11byeast 16.1 70.0 149.9 0.1 4.0 12  CaO 1.5 13a water 369.1 3.1 128.5 1.513b ppt 1.2 1.2 % 97.0% 78.4%  100% reduction^((a))See legend for Table 12.

The data in Table 14 indicate that post-treatment of the liquid streamexiting fermentation step 6 increases the removal of bothphosphorus-containing and nitrogen-containing components compared to theprocesses of Example 21 or 22.

EXAMPLE 24 Process Mass Balance for Barn Waste from a Core Process,Including a Pretreatment of Washed Fiber and a Post Treatment

The procedures of Examples 21 and 22, were followed to prepare the firstextract and the second extract, and the post-treatment procedure ofExample 23 was followed. Analysis for various components was performedat selected steps shown in FIG. 51, and the results are presented inTable 15. TABLE 15 Analysis results from Example 24 at selected steps.Step^((a)) Stream Water^((b)) Sand^((c)) Fiber^((d)) P^((e)) N^((f))COD^((g)) SO₄ ^(2−(h)) Ca^(2+(i)) Yeast^((j)) 1 BW^((k)) 363.3 5.0 9.9104.4 596.4 4,994.5 2 water 14.9  3b sand 2.3 4.5 0.1 1.3 7.4   61.9 4water 39.4  5a liquid 385.2 101.2 578.4 4,844.4  5b solid 19.7 0.5 9.91.8 10.5   88.3  5c liquid 1,970.9 1.2 6 H₂SO₄ 39.4 1.2 9 liquid 365.5101.2 578.4 6,815.2 11a liquid 365.7 17.1 398.1 11b yeast 19.6 84.1180.4 4.9 12  CaO 1.5 13a water 365.7 1.7 119.4 1.5 13b ppt 1.2 1.2 %98.4% 80.0%  100% reduction^((a))See legend for Table 12.

The data in Table 15 indicate that the process including pretreatment ofthe fiber collected from solid/liquid separation step 3 andreintroduction of the extract into the fermentation step 6, andpost-treatment of the combined liquid stream exiting fermentation step 6results in an even higher removal of both phosphorus-containing andnitrogen-containing components compared to any of the processes ofExamples 21, 22, or 23. In addition, the yeast yield was increased overthe process of Examples 21 or 23.

EXAMPLE 25 Process Mass Balance for Barn Waste/Bedding Combination froma Core Process, Including a Pretreatment of Washed Fiber and a PostTreatment

The procedures of Example 24 were followed, except that the barn wasteincluded fiber bedding material (sawdust, straw, etc.). Analysis forvarious components was performed at selected steps shown in FIG. 51, andthe results are presented in Table 16. TABLE 16 Analysis results fromExample 25 at selected steps. Step^((a)) Stream Water^((b)) Sand^((c))Fiber^((d)) P^((e)) N^((f)) COD^((g)) SO₄ ^(2−(h)) Ca^(2+(i))Yeast^((j)) 1 BW^((k)) 356.3 5.0 19.9 104.4 596.4 4,994.5 2 water 14.9 3b sand 2.3 4.5 0.1  1.3 7.5   63.1 4 water 79.4  5a liquid 398.2  99.3567.2 4,750.1  5b solid 39.7 0.5 19.9  3.8 21.7   181.4  5c liquid6,949.0 1.2 6 H₂SO₄ 79.4 1.2 9 liquid 358.5  99.3 567.2 11,699.1  11aliquid 370.3 316.5 11b yeast 27.9 117.3 250.7 7.0 12  CaO 1.5 13a water370.3 31.6 1.5 13b ppt 1.2 1.2 % 100% 94.7%  100% reduction^((a))See legend for Table 12.

The increased carbohydrate from the bedding material resulted in ahigher removal of phosphorus-containing and nitrogen-containingcomponents than Examples, 21, 22, 23, or 24. In addition, the yield ofyeast was higher than Examples, 21, 22, 23, or 24.

It is appreciated that the relative improvements inphosphorus-containing and nitrogen-containing component reduction andyeast yield attributable to the optional pretreatment and/orpost-treatment processes may be better or worse depending upon eachbatch of barn waste, including the amount of bedding material containedtherein. It is further appreciated that the relative improvements inphosphorus-containing and nitrogen-containing component reduction andyeast yield attributable to the optional pretreatment and/orpost-treatment processes may be better or worse depending upon thesource of biomaterial waste.

EXAMPLE 26 Removal of a 29 kDa Protein Spiked into Barn Waste

Samples of barn flush waste were spiked with Bovine Carbonic Anhydrase(BCA, MW 29 kDa) at 1.25 mg/mL. The pH of each was adjusted to 4.0 with30% w/w H₂SO₄ and 100 ppm Al added (aluminum source was aluminumsulfate) and was autoclaved at 121° C. for 10 min. The samples werefiltered through 0.45 μm filter material to remove larger particles,then were fractionated on a Sephadex G-100 gel filtration columnaccording to the following: 2 mL sample on 1.5 cm×˜45 cm column (79 mLcolumn volume) at 2.5 rpm (15 mL/hr). Each fraction was tested forprotein, and the molecular weight (range) determined by a modificationof the micro Lowry method.

Analysis of the fractions showed that the barn flush waste had 4protein/polypeptide peaks of interest when separated on the SephadexG-100. The first peak corresponded to the void volume at fractions 42-56and consisted of proteins 60 kDa and higher. The second peak atfractions 73-102 consisted of proteins having 20-40 kDa. This secondpeak included the spiked in 29 kDa protein, BCA, and was not present inunspiked barn flush waste at detectable levels. The third peak atfractions 106-125 consisted of proteins and polypeptides from 15-1 kDa,and this third peak also was not present in the unspiked barn flushwaste at detectable levels. The last peak at fractions 130-170 containedpolypeptides with molecular weights below 1 kDa that react with theLowry protein method, as shown in Table 17, and in FIG. 52. Referring toFIG. 52, Trace a (•) refers to pH 8, with spiked 29 kDa protein; Trace b(▪) refers to pH 4, 100 ppm Al, heating for 10 min. at 121° C., withspiked 29 kDa protein; Trace c (□) refers to pH 4, 100 ppm Al, no heat,with spiked 29 kDa protein; Trace d (Δ) refers to pH 8, without spiked29 KDa protein; and Trace e (x) refers to pH 4, 100 ppm Al, heating at95° C., without spiked 29 kDa protein.

When the protein spiked barn flush was adjusted to pH 4 with sulfuricacid, and aluminum in the form of aluminum sulfate was added, proteinsover 20 kDa were reduced by 80% to 86%. In this example, the 20 kDaproteins were not totally removed. The reduction in protein wasdetermined to be due in part to precipitation; however, some of thatprotein fraction also was determined to be degraded or broken down tosmaller polypeptides. Peaks 1 and 2 were reduced with the lowering of pHto 4 and the addition of aluminum, but peak 3 increased approximately90%, as shown by Samples (b) and (c) in Table 17, and in FIG. 52.Heating increased the amount of 20 kDa proteins removed by about anadditional 5% to 10%. Heating also increased the amount of highermolecular weight proteins removed by similar amounts. However, heatingincreased the amount of lower molecular weight 15-1 kDa proteins,suggesting some degradation of higher molecular weight proteins. TABLE17 Protein summary of eluted peaks. % Change from Proteins Protein inFractions (mg) Trace a (kDa) Fractions Trace a Trace b Trace c Trace bTrace c ≧60 42-56 1.00 0.05 0.14 −96% −86% (peak 1) 20-40  73-102 5.870.83 1.16 −86% −80% (peak 2) 15-1  106-125 0.65 1.26 0.63 +93%  −3%(peak 3)  <1 130-170 4.40 3.75 3.12 −15% −29% (peak 4)

In addition, lowering the pH and heat the barn flush waste appeared toincrease the solubility of other components, as shown by the inorganicand organic nitrogen results in Table 18. When solids were removed fromthe pH 8 sample, the inorganic and organic nitrogen decreased by 7% and26%, respectively. When acid was added to adjust the sample to pH 4, theinorganic nitrogen was observed to be the same as that of the originalsample before solids were removed, even though the solids were removedfrom the pH 4 sample. When the pH 4+aluminum sample was heated, theorganic nitrogen was reduced 62%, but it was reduced 70% withoutheating. It was observed that although organic nitrogen was decreasedmore without heating, the solids required longer settling times. TABLE18 Nitrogen summary of barn flush waste samples. Inorganic OrganicInorganic Nitrogen Organic Nitrogen Nitrogen (% difference Nitrogen (%difference Sample (mg %) from Trace a) (mg %) from Trace a) Trace a 30 —36 — (before filtration) Trace a 25 −7%  27 −26% (after filtration)Trace b 30 0% 14 −62% (before filtration) Trace b 30 0% 15 −59% (afterfiltration) Trace c 30 0% 11 −70% (after filtration)

The foregoing description, illustrative embodiments, and exemplaryembodiments are intended to illustrate the invention. It is to beunderstood that nothing in the foregoing should be construed to limitthe invention.

1.-45. (canceled)
 46. A process for treating a biomaterial waste streamcomprising swine waste, the process comprising the steps of: providingthe biomaterial waste stream comprising swine waste, and passing saidswine waste through a chopping pump, or analog thereof; separating oneor more solid components from the biomaterial waste stream to provide atreated biomaterial waste stream; hydrolyzing at least a portion of theone or more solid components with an acid; enzymatically degrading atleast a portion of the one or more solid components to prepare a liquidextract; and returning the liquid extract to the treated biomaterialwaste stream.
 47. The process of claim 46 wherein the separating stepincludes separating solid components comprising a biomaterial selectedfrom the group consisting of undigested grain and partially digestedgrain, and combinations thereof.
 48. The process of claim 46 wherein thedegrading step includes contacting the one or more solid components withan acid capable of hydrolyzing celluloses, hemicelluloses,polysaccharides, and oligosaccharides, and combinations thereof.
 49. Theprocess of claim 46 wherein the degrading step includes contacting theone or more solid components with an acid selected from the groupconsisting of sulfuric acid, hydrochloric acid, hydrobromic acid, andphosphoric acid, and combinations thereof.
 50. A process for treating abiomaterial waste stream comprising cheese whey, the process comprisingthe steps of: providing the biomaterial waste stream comprising cheesewhey; adjusting the pH of the waste stream; heating the waste stream toprecipitate one or more solid components comprising protein; separatingthe one or more solid components from the biomaterial waste stream toprovide a treated biomaterial waste stream; degrading at least a portionof the one or more solid components with an acid to prepare a liquidextract; and returning the liquid extract to the treated biomaterialwaste stream.
 51. The process of claim 50 wherein the one or more solidcomponents further comprises carbohydrates.
 52. The process of claim 50wherein the degrading step includes contacting the one or more solidcomponents with an acid selected from the group consisting of sulfuricacid, hydrochloric acid, hydrobromic acid, and phosphoric acid, andcombinations thereof.
 53. The process of claim 50 wherein the degradingstep further includes contacting the one or more solid components withone or more microorganisms capable of degrading lactose.
 54. The processof claim 50 wherein the degrading step further includes contacting theone or more solid components with one or more strains of lactobacillus.55. A process for treating a barn animal biomaterial waste streamcomprising one or more solid cellulosistic components, the processcomprising the steps of: providing the biomaterial waste stream;separating one or more of the solid components from the biomaterialwaste stream to provide a treated biomaterial waste stream; degrading atleast a portion of the one or more solid components with an acid toprepare a liquid extract comprising solubilzed carbohydrate and ligninand polymers thereof; separating the lignin and polymers thereof fromthe liquid extract; and returning the liquid extract to the treatedbiomaterial waste stream.
 56. The process of claim 55 wherein the one ormore solid components comprises a biomaterial selected from the groupconsisting of straw, hay, undigested grain, partially digested grain,and bedding, and combinations thereof.
 57. The process of claim 55wherein the degrading step includes contacting the one or more solidcomponents with an acid selected from the group consisting of sulfuricacid, hydrochloric acid, hydrobromic acid, and phosphoric acid, andcombinations thereof.
 58. An apparatus for separating suspended solidsfrom a biomaterial waste stream, the apparatus comprising: a cylindricalshell having a top and a bottom; an inlet in fluid communication withthe interior volume of the shell, said inlet located at or near thebottom of the shell, and protruding into the interior volume of theshell; an outlet in fluid communication with the interior volume of theshell, said outlet located at or near the top of the shell a solidoutlet located at or near the bottom of the shell in fluid communicationwith interior volume of the shell; one or more stackable inner cylindersdisposed in the shell, where the one or more inner cylinders include atruncated cone top having an opening, and at least a partially openbottom; and a conical disk positioned about centrally within the innercylinder, said disk being attached to the inner surface of the innercylinder; where the inner cylinders are sized and positioned to createand substantially maintain a gap between the inner surface of the shelland the outer surface of the inner cylinder, said gap having dimensionsgreater than the dimensions of the suspended solids to allow aidparticles to flow counter currently to the direction of flow of themajority of the biomaterial waste stream.
 59. The apparatus of claim 58wherein there are a plurality of inner cylinders.
 60. The apparatus ofclaim 58 wherein the bottom of the one or more inner cylinders issubstantially open.
 61. The apparatus of claim 58 wherein the opening inthe top of the one or more inner cylinders is substantially centeredrelative to the vertical axis of the inner cylinder.
 62. The apparatusof claim 58 wherein the conical disk is substantially centered relativeto the vertical axis of the inner cylinder.
 63. The apparatus of claim59 wherein the truncated cone top of at least one inner cylinderprotrudes into the open bottom of one other inner cylinder.
 64. Theapparatus of claim 58 wherein the truncated cone top forms a shallowslope angle relative to the cylindrical sides of the inner cylinder. 65.The apparatus of claim 58 further comprising a disperser configured tocreate a vortex in the biomaterial waste stream under flow conditions.